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	Author	Turner, S.; Lu, Y.-G.; Janssens, S.D.; da Pieve, F.; Lamoen, D.; Verbeeck, J.; Haenen, K.; Wagner, P.; Van Tendeloo, G.
	Title	Local boron environment in B-doped nanocrystalline diamond films			Type	A1 Journal article
	Year	2012	Publication	Nanoscale	Abbreviated Journal	Nanoscale
	Volume	4	Issue	19	Pages	5960-5964
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Thin films of heavily B-doped nanocrystalline diamond (B:NCD) have been investigated by a combination of high resolution annular dark field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy performed on a state-of-the-art aberration corrected instrument to determine the B concentration, distribution and the local B environment. Concentrations of [similar]1 to 3 at.% of boron are found to be embedded within individual grains. Even though most NCD grains are surrounded by a thin amorphous shell, elemental mapping of the B and C signal shows no preferential embedding of B in these amorphous shells or in grain boundaries between the NCD grains, in contrast with earlier work on more macroscopic superconducting polycrystalline B-doped diamond films. Detailed inspection of the fine structure of the boron K-edge and comparison with density functional theory calculated fine structure energy-loss near-edge structure signatures confirms that the B atoms present in the diamond grains are substitutional atoms embedded tetrahedrally into the diamond lattice.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000308705900026	Publication Date	2012-08-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2040-3364;2040-3372;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.367	Times cited	39	Open Access
	Notes	FWO G056810N; GOA XANES meets ELNES; 246791 COUNTATOMS; Hercules; 262348 ESMI; Methusalem Nano			Approved	Most recent IF: 7.367; 2012 IF: 6.233
	Call Number	UA @ lucian @ c:irua:101227UA @ admin @ c:irua:101227			Serial	1825
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	Author	Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G.
	Title	Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared			Type	A1 Journal article
	Year	2017	Publication	Nature communications	Abbreviated Journal	Nat Commun
	Volume	8	Issue	8	Pages	14925
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000397799700001	Publication Date	2017-03-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-1723	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	12.124	Times cited	37	Open Access	OpenAccess
	Notes	The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara			Approved	Most recent IF: 12.124
	Call Number	EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203			Serial	4538
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	Author	Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.; van Speybroeck, V.; Waroquier, M.
	Title	Electronic structure and band gap of zinc spinel oxides beyond LDA : ZnAl₂O₄, ZnGa₂O₄ and ZnIn₂O₄			Type	A1 Journal article
	Year	2011	Publication	New journal of physics	Abbreviated Journal	New J Phys
	Volume	13	Issue	6	Pages	063002-063002,11
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We examine the electronic structure of the family of ternary zinc spinel oxides ZnX2O4 (X=Al, Ga and In). The band gap of ZnAl2O4 calculated using density functional theory (DFT) is 4.25 eV and is overestimated compared with the experimental value of 3.83.9 eV. The DFT band gap of ZnGa2O4 is 2.82 eV and is underestimated compared with the experimental value of 4.45.0 eV. Since DFT typically underestimates the band gap in the oxide system, the experimental measurements for ZnAl2O4 probably require a correction. We use two first-principles techniques capable of describing accurately the excited states of semiconductors, namely the GW approximation and the modified BeckeJohnson (MBJ) potential approximation, to calculate the band gap of ZnX2O4. The GW and MBJ band gaps are in good agreement with each other. In the case of ZnAl2O4, the predicted band gap values are >6 eV, i.e. ~2 eV larger than the only reported experimental value. We expect future experimental work to confirm our results. Our calculations of the electron effective masses and the second band gap indicate that these compounds are very good candidates to act as transparent conducting host materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000292137500002	Publication Date	2011-06-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1367-2630;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.786	Times cited	98	Open Access
	Notes	Iwt; Fwo; Bof-Noi			Approved	Most recent IF: 3.786; 2011 IF: 4.177
	Call Number	UA @ lucian @ c:irua:89555			Serial	1008
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	Author	Soldatov, A.; Yalovega, G.; Smolentsev, G.; Kravtsova, A.; Lamoen, D.; Balasubramanian, C.; Marcelli, A.; Cinque, G.; Bellucci, S.
	Title	ALN nanoparticles XANES analysis: local atomic and electronic structure			Type	A1 Journal article
	Year	2007	Publication	Nuclear Instruments & Methods In Physics Research Section A-Accelerators Spectrometers Detectors And Associated Equipment	Abbreviated Journal	Nucl Instrum Meth A
	Volume	575	Issue	1/2	Pages	85-87
	Keywords	A1 Journal article; Electron Microscopy for Materials Science (EMAT);
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Elsevier	Place of Publication	Amsterdam	Editor
	Language		Wos	000247146600021	Publication Date	2007-01-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0168-9002;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.362	Times cited	3	Open Access
	Notes				Approved	Most recent IF: 1.362; 2007 IF: 1.114
	Call Number	UA @ lucian @ c:irua:64755			Serial	89
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	Author	Lamoen, D.; Michel, K.H.
	Title	Coupling of orientational and translational modes in solid C60 and C70			Type	A1 Journal article
	Year	1999	Publication	Phase transitions	Abbreviated Journal	Phase Transit
	Volume	67	Issue		Pages	789
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York	Editor
	Language		Wos	000079806300017	Publication Date	2007-07-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0141-1594;1029-0338;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.06	Times cited	2	Open Access
	Notes				Approved	Most recent IF: 1.06; 1999 IF: 0.622
	Call Number	UA @ lucian @ c:irua:27830			Serial	537
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	Author	Turner, S.; Shenderova, O.; da Pieve, F.; Lu, Y.-G.; Yücelen, E.; Verbeeck, J.; Lamoen, D.; Van Tendeloo, G.
	Title	Aberration-corrected microscopy and spectroscopy analysis of pristine, nitrogen containing detonation nanodiamond			Type	A1 Journal article
	Year	2013	Publication	Physica status solidi : A : applications and materials science	Abbreviated Journal	Phys Status Solidi A
	Volume	210	Issue	10	Pages	1976-1984
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Aberration-corrected transmission electron microscopy, electron energy-loss spectroscopy, and density functional theory (DFT) calculations are used to solve several key questions about the surface structure, the particle morphology, and the distribution and nature of nitrogen impurities in detonation nanodiamond (DND) cleaned by a recently developed ozone treatment. All microscopy and spectroscopy measurements are performed at a lowered acceleration voltage (80/120kV), allowing prolonged and detailed experiments to be carried out while minimizing the risk of knock-on damage or surface graphitization of the nanodiamond. High-resolution TEM (HRTEM) demonstrates the stability of even the smallest nanodiamonds under electron illumination at low voltage and is used to image the surface structure of pristine DND. High resolution electron energy-loss spectroscopy (EELS) measurements on the fine structure of the carbon K-edge of nanodiamond demonstrate that the typical * pre-peak in fact consists of three sub-peaks that arise from the presence of, amongst others, minimal fullerene-like reconstructions at the nanoparticle surfaces and deviations from perfect sp(3) coordination at defects in the nanodiamonds. Spatially resolved EELS experiments evidence the presence of nitrogen within the core of DND particles. The nitrogen is present throughout the whole diamond core, and can be enriched at defect regions. By comparing the fine structure of the experimental nitrogen K-edge with calculated energy-loss near-edge structure (ELNES) spectra from DFT, the embedded nitrogen is most likely related to small amounts of single substitutional and/or A-center nitrogen, combined with larger nitrogen clusters.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000329299700025	Publication Date	2013-10-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1862-6300;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.775	Times cited	37	Open Access
	Notes	262348 ESMI; 246791 COUNTATOMS; FWO; Hercules; GOA XANES meets ELNES			Approved	Most recent IF: 1.775; 2013 IF: 1.525
	Call Number	UA @ lucian @ c:irua:110821UA @ admin @ c:irua:110821			Serial	41
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	Author	Titantah, J.T.; Lamoen, D.
	Title	First-principles characterization of amorphous carbon nitride systems: structural and electronic properties			Type	A1 Journal article
	Year	2006	Publication	Physica status solidi: A: applied research	Abbreviated Journal	Phys Status Solidi A
	Volume	203	Issue	12	Pages	3191-3197
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Berlin	Editor
	Language		Wos	000240967400032	Publication Date	2006-09-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1862-6300;1862-6319;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.775	Times cited	3	Open Access
	Notes				Approved	Most recent IF: 1.775; 2006 IF: NA
	Call Number	UA @ lucian @ c:irua:61003			Serial	1205
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	Author	Titantah, J.T.; Lamoen, D.
	Title	A technique for the sp2/sp3 characterization of carbon materials			Type	A1 Journal article
	Year	2004	Publication	Physica status solidi: A: applied research	Abbreviated Journal	Phys Status Solidi A
	Volume	201	Issue		Pages	2492
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Berlin	Editor
	Language		Wos	000224152700019	Publication Date	2004-09-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-8965;1521-396X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	2	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:49656			Serial	3472
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	Author	Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.; Volety, K.; Huyberechts, G.; Paul, J.
	Title	High throughput first-principles calculations of bixbyite oxides for TCO applications			Type	A1 Journal article
	Year	2014	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	16	Issue	33	Pages	17724-17733
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We present a high-throughput computing scheme based on density functional theory (DFT) to generate a class of oxides and screen them with the aim of identifying those that might be electronically appropriate for transparent conducting oxide (TCO) applications. The screening criteria used are a minimum band gap to ensure sufficient transparency, a band edge alignment consistent with easy n- or p-type dopability, and a minimum thermodynamic phase stability to be experimentally synthesizable. Following this scheme we screened 23 binary and 1518 ternary bixbyite oxides in order to identify promising candidates, which can then be a subject of an in-depth study. The results for the known TCOs are in good agreement with the reported data in the literature. We suggest a list of several new potential TCOs, including both n- and p-type compounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000341064800041	Publication Date	2014-07-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076;1463-9084;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	23	Open Access
	Notes	; We gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project (IWT-n 080023), the FWO-Vlaanderen through project G.0150.13 and a GOA fund from the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation and the Flemish Government (EWI Department). ;			Approved	Most recent IF: 4.123; 2014 IF: 4.493
	Call Number	UA @ lucian @ c:irua:118263			Serial	1469
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	Author	Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D.
	Title	Native point defects in CuIn_1-xGa_xSe₂ : hybrid density functional calculations predict the origin of p- and n-type conductivity			Type	A1 Journal article
	Year	2014	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	16	Issue	40	Pages	22299-22308
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We have performed a first-principles study of the p- and n-type conductivity in CuIn1−xGaxSe2 due to native point defects, based on the HSE06 hybrid functional. Band alignment shows that the band gap becomes larger with x due to the increasing conduction band minimum, rendering it hard to establish n-type conductivity in CuGaSe2. From the defect formation energies, we find that In/GaCu is a shallow donor, while VCu, VIn/Ga and CuIn/Ga act as shallow acceptors. Using the total charge neutrality of ionized defects and intrinsic charge carriers to determine the Fermi level, we show that under In-rich growth conditions InCu causes strongly n-type conductivity in CuInSe2. Under increasingly In-poor growth conditions, the conductivity type in CuInSe2 alters to p-type and compensation of the acceptors by InCu reduces, as also observed in photoluminescence experiments. In CuGaSe2, the native acceptors pin the Fermi level far away from the conduction band minimum, thus inhibiting n-type conductivity. On the other hand, CuGaSe2 shows strong p-type conductivity under a wide range of Ga-poor growth conditions. Maximal p-type conductivity in CuIn1−xGaxSe2 is reached under In/Ga-poor growth conditions, in agreement with charge concentration measurements on samples with In/Ga-poor stoichiometry, and is primarily due to the dominant acceptor CuIn/Ga.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000343072800042	Publication Date	2014-09-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076;1463-9084;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	43	Open Access
	Notes	; We gratefully acknowledge financial support from the science fund FWO-Flanders through project G.0150.13. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules foundation and the Flemish Government (EWI Department). We also like to thank Prof. S. Siebentritt of the University of Luxembourg for a presentation of her work on GIGS during a visit to our research group and for helpful discussions of our results. ;			Approved	Most recent IF: 4.123; 2014 IF: 4.493
	Call Number	UA @ lucian @ c:irua:120465			Serial	2284
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	Author	Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	The origin of p-type conductivity in ZnM₂O₄ (M = Co, Rh, Ir) spinels			Type	A1 Journal article
	Year	2014	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	16	Issue	6	Pages	2588-2596
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000329926700040	Publication Date	2013-12-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076;1463-9084;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	47	Open Access
	Notes	Fwo; Goa; Hercules			Approved	Most recent IF: 4.123; 2014 IF: 4.493
	Call Number	UA @ lucian @ c:irua:114829			Serial	2525
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	Author	Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	The role of the V_Zn-N_O-H complex in the p-type conductivity in ZnO			Type	A1 Journal article
	Year	2015	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	17	Issue	17	Pages	5485-5489
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000349616400080	Publication Date	2015-01-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076;1463-9084;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	20	Open Access
	Notes	FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules			Approved	Most recent IF: 4.123; 2015 IF: 4.493
	Call Number	c:irua:123218			Serial	3592
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	Author	Bercx, M.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.
	Title	First-principles analysis of the spectroscopic limited maximum efficiency of photovoltaic absorber layers for CuAu-like chalcogenides and silicon			Type	A1 Journal article
	Year	2016	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	18	Issue	18	Pages	20542-20549
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Chalcopyrite semiconductors are of considerable interest for application as absorber layers in thin-film photovoltaic cells. When growing films of these compounds, however, they are often found to contain CuAu-like domains, a metastable phase of chalcopyrite. It has been reported that for CuInS2, the presence of the CuAu-like phase improves the short circuit current of the chalcopyrite-based photovoltaic cell. We investigate the thermodynamic stability of both phases for a selected list of I-III-VI2 materials using a first-principles density functional theory approach. For the CuIn-VI2 compounds, the difference in formation energy between the chalcopyrite and CuAu-like phase is found to be close to 2 meV per atom, indicating a high likelihood of the presence of CuAu-like domains. Next, we calculate the spectroscopic limited maximum efficiency (SLME) of the CuAu-like phase and compare the results with those of the corresponding chalcopyrite phase. We identify several candidates with a high efficiency, such as CuAu-like CuInS2, for which we obtain an SLME of 29% at a thickness of 500 nm. We observe that the SLME can have values above the Shockley-Queisser (SQ) limit, and show that this can occur because the SQ limit assumes the absorptivity to be a step function, thus overestimating the radiative recombination in the detailed balance approach. This means that it is possible to find higher theoretical efficiencies within this framework simply by calculating the J-V characteristic with an absorption spectrum. Finally, we expand our SLME analysis to indirect band gap absorbers by studying silicon, and find that the SLME quickly overestimates the reverse saturation current of indirect band gap materials, drastically lowering their calculated efficiency.
	Address	EMAT & CMT groups, Department of Physics, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171, 2020 Antwerp, Belgium. marnik.bercx@uantwerpen.be
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Wos	000381428600058	Publication Date	2016-07-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	34	Open Access
	Notes	We acknowledge financial support of FWO-Vlaanderen through projects G.0150.13N and G.0216.14N and ERA-NET RUS Plus/FWO, Grant G0D6515N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO FWOVlaanderen.			Approved	Most recent IF: 4.123
	Call Number	c:irua:135091			Serial	4112
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	Author	Matsubara, M.; Saniz, R.; Partoens, B.; Lamoen, D.
	Title	Doping anatase TiO₂with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study			Type	A1 Journal article
	Year	2017	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	19	Issue	19	Pages	1945-1952
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We investigate the role of transition metal atoms of group V-b (V, Nb, Ta) and VI-b (Cr, Mo, W) as n- or p-type dopants in anatase TiO$2$ using thermodynamic principles and density functional theory with the Heyd-Scuseria-Ernzerhof HSE06 hybrid functional. The HSE06 functional provides a realistic value for the band gap, which ensures a correct classification of dopants as shallow or deep donors or acceptors. Defect formation energies and thermodynamic transition levels are calculated taking into account the constraints imposed by the stability of TiO$2$ and the solubility limit of the impurities. Nb, Ta, W and Mo are identified as shallow donors. Although W provides two electrons, Nb and Ta show a considerable lower formation energy, in particular under O-poor conditions. Mo donates in principle one electron, but under specific conditions can turn into a double donor. V impurities are deep donors and Cr shows up as an amphoteric defect, thereby acting as an electron trapping center in n-type TiO$_2$ especially under O-rich conditions. A comparison with the available experimental data yields excellent agreement.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000394426400027	Publication Date	2016-12-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	19	Open Access	OpenAccess
	Notes	We gratefully acknowledge financial support from the IWTVlaanderenthrough projects G.0191.08 and G.0150.13, and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation. M. M. acknowledges financial support from the GOA project ‘‘XANES meets ELNES’’ of the University of Antwerp.			Approved	Most recent IF: 4.123
	Call Number	EMAT @ emat @ c:irua:140835			Serial	4421
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	Author	Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D.
	Title	Structural and electronic properties of defects at grain boundaries in CuInSe₂			Type	A1 Journal article
	Year	2017	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	19	Issue	19	Pages	14770-14780
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000403327200059	Publication Date	2017-05-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	12	Open Access	OpenAccess
	Notes	We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI.			Approved	Most recent IF: 4.123
	Call Number	EMAT @ emat @ c:irua:143869			Serial	4577
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	Author	Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K.
	Title	A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc			Type	A1 Journal article
	Year	2017	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	19	Issue	40	Pages	27866-27877
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A combined experimental and first-principles study is performed to study the origin of conductivity in ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR) and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been discussed in the literature to date. However, our first-principles calculations show that such a complex is indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly also form Zn clusters, leading to the observed increased conductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000413290500073	Publication Date	2017-10-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	26	Open Access	OpenAccess
	Notes	We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department).			Approved	Most recent IF: 4.123
	Call Number	EMAT @ emat @c:irua:146878			Serial	4760
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	Author	Matsubara, M.; Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	Attracting shallow donors : hydrogen passivation in (Al,Ga,In)-doped ZnO			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	86	Issue	16	Pages	165207
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	The hydrogen interstitial and the substitutional AlZn, GaZn, and InZn are all shallow donors in ZnO and lead to n-type conductivity. Although shallow donors are expected to repel each other, we show by first-principles calculations that in ZnO these shallow donor impurities attract and form a complex, leading to a donor level deep in the band gap. This puts a limit on the n-type conductivity of (Al,Ga,In)-doped ZnO in the presence of hydrogen.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000310131300008	Publication Date	2012-10-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	7	Open Access
	Notes	Iwt; Fwo; Bof-Noi			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:101780			Serial	202
Permanent link to this record



	Author	Titantah, J.T.; Jorissen, K.; Lamoen, D.
	Title	Density functional theory calculations of energy-loss carbon near-edge spectra of small diameter armchair and zigzag nanotubes: core-hole, curvature, and momentum-transfer orientation effects			Type	A1 Journal article
	Year	2004	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	69	Issue		Pages	125406,1-11
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000221259000113	Publication Date	2004-03-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	28	Open Access
	Notes				Approved	Most recent IF: 3.836; 2004 IF: 3.075
	Call Number	UA @ lucian @ c:irua:45626			Serial	637
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	Author	Titantah, J.T.; Lamoen, D.
	Title	Determination of the electron effective band mass in amorphous carbon from density-functional theory calculations			Type	A1 Journal article
	Year	2004	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	70	Issue		Pages	033101,1-4
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000222996700001	Publication Date	2004-07-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	24	Open Access
	Notes				Approved	Most recent IF: 3.836; 2004 IF: 3.075
	Call Number	UA @ lucian @ c:irua:49655			Serial	676
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	Author	Govaerts, K.; Park, K.; De Beule, C.; Partoens, B.; Lamoen, D.
	Title	Effect of Bi bilayers on the topological states of Bi₂Se₃ : a first-principles study			Type	A1 Journal article
	Year	2014	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	90	Issue	15	Pages	155124
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Bi2Se3 is a three-dimensional topological insulator which has been extensively studied because it has a single Dirac cone on the surface, inside a relatively large bulk band gap. However, the effect of two-dimensional topological insulator Bi bilayers on the properties of Bi2Se3 and vice versa, has not been explored much. Bi bilayers are often present between the quintuple layers of Bi2Se3, since (Bi2)n(Bi2Se3)m form stable ground-state structures. Moreover, Bi2Se3 is a good substrate for growing ultrathin Bi bilayers. By first-principles techniques, we first show that there is no preferable surface termination by either Bi or Se. Next, we investigate the electronic structure of Bi bilayers on top of, or inside a Bi2Se3 slab. If the Bi bilayers are on top, we observe a charge transfer to the quintuple layers that increases the binding energy of the surface Dirac cones. The extra states, originating from the Bi bilayers, were declared to form a topological Dirac cone, but here we show that these are ordinary Rashba-split states. This result, together with the appearance of a new Dirac cone that is localized slightly deeper, might necessitate the reinterpretation of several experimental results. When the Bi bilayers are located inside the Bi2Se3 slab, they tend to split the slab into two topological insulators with clear surface states. Interface states can also be observed, but an energy gap persists because of strong coupling between the neighboring quintuple layers and the Bi bilayers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000343773200001	Publication Date	2014-10-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	30	Open Access
	Notes	; We gratefully acknowledge financial support from the Research Foundation – Flanders (FWO-Vlaanderen). K.G. thanks the University of Antwerp for a Ph.D. fellowship. C.D.B. is an aspirant of the Flemish Science Foundation. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules Foundation and the Flemish Government (EWI Department). K.P. was supported by U.S. National Science Foundation Grant No. DMR-1206354. ;			Approved	Most recent IF: 3.836; 2014 IF: 3.736
	Call Number	UA @ lucian @ c:irua:119527			Serial	800
Permanent link to this record



	Author	Potapov, P.L.; Jorissen, K.; Schryvers, D.; Lamoen, D.
	Title	Effect of charge transfer on EELS integrated cross sections in Mn and Ti oxides			Type	A1 Journal article
	Year	2004	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	70	Issue		Pages	045106,1-10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000223053300016	Publication Date	2004-07-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	28	Open Access
	Notes				Approved	Most recent IF: 3.836; 2004 IF: 3.075
	Call Number	UA @ lucian @ c:irua:47333			Serial	803
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	Author	Verbeeck, J.; Bals, S.; Lamoen, D.; Luysberg, M.; Huijben, M.; Rijnders, G.; Brinkman, A.; Hilgenkamp, H.; Blank, D.H.A.; Van Tendeloo, G.
	Title	Electronic reconstruction at n-type SrTiO₃/LaAlO₃ interfaces			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	8	Pages	085113,1-085113,6
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Electron-energy-loss spectroscopy (EELS) is used to investigate single layers of LaAlO3 grown on SrTiO3 having an n-type interface as well as multilayers of LaAlO3 and SrTiO3 in which both n- and p-type interfaces occur. Only minor changes in Ti valence at the n-type interface are observed. This finding seems to contradict earlier experiments for other SrTiO3/LaAlO3 systems where large deviations in Ti valency were assumed to be responsible for the conductivity of these interfaces. Ab initio calculations have been carried out in order to interpret our EELS results. Using the concept of Bader charges, it is demonstrated that the so-called polar discontinuity is mainly resolved by lattice distortions and to a far lesser extent by changes in valency for both single layer and multilayer geometries.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000275053300040	Publication Date	2010-02-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	25	Open Access
	Notes	Esteem 026019; Fwo			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:81768UA @ admin @ c:irua:81768			Serial	1005
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	Author	Titantah, J.T.; Lamoen, D.
	Title	Energy-loss near-edge structure changes with bond length in carbon systems			Type	A1 Journal article
	Year	2005	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	72	Issue	19	Pages	193104,1-4
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000233603700004	Publication Date	2005-11-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	24	Open Access
	Notes				Approved	Most recent IF: 3.836; 2005 IF: 3.185
	Call Number	UA @ lucian @ c:irua:56050			Serial	1041
Permanent link to this record



	Author	Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	Erratum : First-principles study of possible shallow donors in ZnAl₂O₄ spinel [Phys. Rev. B 87, 174101 (2013)]			Type	A1 Journal article
	Year	2013	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	88	Issue	5	Pages	059905-2
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000323572600009	Publication Date	2013-08-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	1	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836; 2013 IF: 3.664
	Call Number	UA @ lucian @ c:irua:110015			Serial	1080
Permanent link to this record



	Author	Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	First-principles study of possible shallow donors in ZnAl₂O₄ spinel			Type	A1 Journal article
	Year	2013	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	87	Issue	17	Pages	174101-174107
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	ZnAl2O4 (gahnite) is a ceramic which is considered a possible transparent conducting oxide (TCO) due to its wide band gap and transparency for UV. Defects play an important role in controlling the conductivity of a TCO material along with the dopant, which is the main source of conductivity in an otherwise insulating oxide. A comprehensive first-principles density functional theory study for point defects in ZnAl2O4 spinel is presented using the Heyd, Scuseria, and Ernzerhof hybrid functional (HSE06) to overcome the band gap problem. We have investigated the formation energies of intrinsic defects which include the Zn, Al, and O vacancy and the antisite defects: Zn at the Al site (ZnAl) and Al at the Zn site (AlZn). The antisite defect AlZn has the lowest formation energy and acts as a shallow donor, indicating possible n-type conductivity in ZnAl2O4 spinel by Al doping.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000318653300001	Publication Date	2013-05-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	50	Open Access
	Notes	Iwt; Fwo			Approved	Most recent IF: 3.836; 2013 IF: 3.664
	Call Number	UA @ lucian @ c:irua:108769			Serial	1219
Permanent link to this record



	Author	Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D.
	Title	Homologous series of layered structures in binary and ternary Bi-Sb-Te-Se systems : ab initio study			Type	A1 Journal article
	Year	2014	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	89	Issue	5	Pages	054106-54109
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	In order to account explicitly for the existence of long-periodic layered structures and the strong structural relaxations in the most common binary and ternary alloys of the Bi-Sb-Te-Se system, we have developed a one-dimensional cluster expansion (CE) based on first-principles electronic structure calculations, which accounts for the Bi and Sb bilayer formation. Excellent interlayer distances are obtained with a van der Waals density functional. It is shown that a CE solely based on pair interactions is sufficient to provide an accurate description of the ground-state energies of Bi-Sb-Te-Se binary and ternary systems without making the data set of ab initio calculated structures unreasonably large. For the binary alloys A1−xQx (A=Sb, Bi; Q=Te, Se), a ternary CE yields an almost continuous series of (meta)stable structures consisting of consecutive A bilayers next to consecutive A2Q3 for 0<x<0.6. For x>0.6, the binary alloy segregates into pure Q and A2Q3. The Bi-Sb system is described by a quaternary CE and is found to be an ideal solid solution stabilized by entropic effects at T≠0 K but with an ordered structure of alternating Bi and Sb layers for x=0.5 at T=0 K. A quintuple CE is used for the ternary Bi-Sb-Te system, where stable ternary layered compounds with an arbitrary stacking of Sb2Te3, Bi2Te3, and Te-Bi-Te-Sb-Te quintuple units are found, optionally separated by mixed Bi/Sb bilayers. Electronic properties of the stable compounds were studied taking spin-orbit coupling into account.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000332420900001	Publication Date	2014-03-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes	Fwo; Hercules			Approved	Most recent IF: 3.836; 2014 IF: 3.736
	Call Number	UA @ lucian @ c:irua:114910			Serial	1487
Permanent link to this record



	Author	Sarmadian, N.; Saniz, R.; Lamoen, D.; Partoens, B.
	Title	Influence of Al concentration on the optoelectronic properties of Al-doped MgO			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	86	Issue	20	Pages	205129-5
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	We use density functional theory within the local density approximation to investigate the structural, electronic, and optical properties of Al-doped MgO. The concentrations considered range from 6% to 56%. In the latter case, we also compare the optical properties of the amorphous and crystalline phases. We find that, overall, the electronic properties of the crystalline phases change qualitatively little with Al concentration. On the other hand, the changes in the electronic structure in the amorphous phase are more important, most notably because of deep impurity levels in the band gap that are absent in the crystalline phase. This leads to observable effects in, e.g., the optical absorption edge and in the refractive index. Thus, the latter can be used to characterize the crystalline to amorphous transition with Al doping level.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000311605000003	Publication Date	2012-11-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes	Iwt; Fwo			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:105137			Serial	1612
Permanent link to this record



	Author	Lamoen, D.; Michel, K.H.
	Title	Microscopic theory of thermoelastic phenomena and pressure dependence in solid C₆₀			Type	A1 Journal article
	Year	1993	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	48	Issue	2	Pages	807-813
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A microscopic theory for the coupling of molecular orientations with acoustic lattice displacements is proposed. The relevant interaction is quadratic in the orientational-order-parameter variables and linear in longitudinal strains. The coupling is evaluated for a complex molecular structure. The intermolecular potential is obtained from interaction centers placed at nuclei and at the centers of interatomic bonds. The free energy is derived and the experimental consequences of the theory are studied. The Clausius-Clapeyron equation for orientational melting is obtained. The theory explains the decrease of the lattice constant at the first-order phase transition and the increase of the transition temperature with applied pressure.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	A1993LM88500014	Publication Date	2002-07-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0163-1829;1095-3795;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.736	Times cited	32	Open Access
	Notes				Approved	PHYSICS, CONDENSED MATTER 16/67 Q1 #
	Call Number	UA @ lucian @ c:irua:5779			Serial	2035
Permanent link to this record



	Author	Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
	Title	Size effects and strain state of Ga_1-xIn_xAs/GaAs multiple quantum wells: Monte Carlo study			Type	A1 Journal article
	Year	2008	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	78	Issue	16	Pages	165326,1-165326,7
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The effect of the size of the GaAs barrier and the Ga1−xInxAs well on the structural properties of a Ga1−xInxAs/GaAs multiple quantum well structure is investigated using the Metropolis Monte Carlo approach based on a well-parametrized Tersoff potential. It is found that within the well the Ga-As and In-As bond lengths undergo contractions whose magnitude increases with increasing In content in sharp contrast with bond-length variations in the bulk Ga1−xInxAs systems. For fixed barrier size and In content, the contraction of the bonds is also found to increase with increasing size of the well. Using the local atomic structure of the heterostructures, a more local analysis of the strain state of the systems is given and comparison with the prediction of macroscopic continuum elasticity theory shows deviations from the latter.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000260574500084	Publication Date	2008-10-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes				Approved	Most recent IF: 3.836; 2008 IF: 3.322
	Call Number	UA @ lucian @ c:irua:72920			Serial	3036
Permanent link to this record



	Author	Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D.
	Title	Stability of Sb-Te layered structures : first-principles study			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144114-144114,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303115400004	Publication Date	2012-04-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	Iwt; Fwo			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98255			Serial	3129
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