Records |
Author |
Retuerto, M.; Skiadopoulou, S.; Li, M.R.; Abakumov, A.M.; Croft, M.; Ignatov, A.; Sarkar, T.; Abbett, B.M.; Pokorný, J.; Savinov, M.; Nuzhnyy, D.; Prokleška, J.; Abeykoon, M.; Stephens, P.W.; Hodges, J.P.; Vaněk, P.; Fennie, C.J.; Rabe, K.M.; Kamba, S.; Greenblatt, M.; |
Title |
Pb2MnTeO6 double perovskite : an antipolar anti-ferromagnet |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
55 |
Issue |
55 |
Pages |
4320-4329 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Pb2MnTeO6, a new double perovskite, was synthesized. Its crystal structure was determined by synchrotron X-ray and powder neutron diffraction. Pb2MnTeO6 is monoclinic (I2/m) at room temperature with a regular arrangement of all the cations in their polyhedra. However, when the temperature is lowered to similar to 120 K it undergoes a phase transition from I2/m to C2/c structure. This transition is accompanied by a displacement of the Pb atoms from the center of their polyhedra due to the 6s2 lone-pair electrons, together with a surprising off-centering of Mn2+ (d5) magnetic cations. This strong first-order phase transition is also evidenced by specific heat, dielectric, Raman, and infrared spectroscopy measurements. The magnetic characterizations indicate an anti-ferromagnetic (AFM) order below TN approximate to 20 K; analysis of powder neutron diffraction data confirms the magnetic structure with propagation vector k = (0 1 0) and collinear AFM spins. The observed jump in dielectric permittivity near similar to 150 K implies possible anti-ferroelectric behavior; however, the absence of switching suggests that Pb2MnTeO6 can only be antipolar. First-principle calculations confirmed that the crystal and magnetic structures determined are locally stable and that anti-ferroelectric switching is unlikely to be observed in Pb2MnTeO6. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000375519700027 |
Publication Date |
2016-04-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857 |
Call Number |
UA @ lucian @ c:irua:134219 |
Serial |
4258 |
Permanent link to this record |
|
|
|
Author |
Morozov, V.A.; Raskina, M.V.; Lazoryak, B.I.; Meert, K.W.; Korthout, K.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.; |
Title |
Crystal Structure and Luminescent Properties of R2-xEux(MoO4)(3) (R = Gd, Sm) Red Phosphors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
24 |
Pages |
7124-7136 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The R-2(MoO4)(3) (R = rare earth elements) molybdates doped with Eu3+ cations are interesting red-emitting materials for display and solid-state lighting applications. The structure and luminescent properties of the R2-xEux(MoO4)(3) (R = Gd, Sm) solid solutions have been investigated as a function of chemical composition and preparation conditions. Monoclinic (alpha) and orthorhombic (beta') R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) modifications were prepared by solid-state reaction, and their structures were investigated using synchrotron powder X-ray diffraction and transmission electron microscopy. The pure orthorhombic beta'-phases could be synthesized only by quenching from high temperature to room temperature for Gd2-xEux(MoO4)(3) in the Eu3+-rich part (x > 1) and for all Sm2-xEux(MoO4)(3) solid solutions. The transformation from the alpha-phase to the beta'-phase results in a notable increase (similar to 24%) of the unit cell volume for all R2-xEux(MoO4)(3) (R = Sm, Gd) solid solutions. The luminescent properties of all R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) solid solutions were measured, and their optical properties were related to their structural properties. All R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) phosphors emit intense red light dominated by the D-5(0)-> F-7(2) transition at similar to 616 nm. However, a change in the multiplet splitting is observed when switching from the monoclinic to the orthorhombic structure, as a consequence of the change in coordination polyhedron of the luminescent ion from RO8 to RO7 for the alpha- and beta'-modification, respectively. The Gd2-xEux(MoO4)(3) solid solutions are the most efficient emitters in the range of 0 < x < 1.5, but their emission intensity is comparable to or even significantly lower than that of Sm2-xEux(MoO4)(3) for higher Eu3+ concentrations (1.5 <= x <= 1.75). Electron energy loss spectroscopy (EELS) measurements revealed the influence of the structure and element content on the number and positions of bands in the ultraviolet-visible-infrared regions of the EELS spectrum. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000347139700027 |
Publication Date |
2014-11-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
24 |
Open Access |
|
Notes |
Fwo G039211n; G004413n; 278510 Vortex ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:122829UA @ admin @ c:irua:122829 |
Serial |
558 |
Permanent link to this record |
|
|
|
Author |
Morozov, V.A.; Bertha, A.; Meert, K.W.; Van Rompaey, S.; Batuk, D.; Martinez, G.T.; Van Aert, S.; Smet, P.F.; Raskina, M.V.; Poelman, D.; Abakumov, A.M.; Hadermann, J.; |
Title |
Incommensurate modulation and luminescence in the CaGd2(1-x)Eu2x(MoO4)4(1-y)(WO)4y (0\leq x\leq1, 0\leq y\leq1) red phosphors |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
25 |
Issue |
21 |
Pages |
4387-4395 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Scheelite related compounds (A',A '') [(B',B '')O-4], with B', B '' = W and/or Mo are promising new light-emitting materials for photonic applications, including phosphor converted LEDs (light-emitting diodes). In this paper, the creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescent properties. CaGd2(1-x)Eu2x(MoO4)(4(1-y))(WO4)(4y) (0 <= x <= 1, 0 <= y <= 1) solid solutions with scheelite-type structure were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder X-ray diffraction. Within this series all complex molybdenum oxides have (3 + 2)D incommensurately modulated structures with superspace group I4(1)/a(alpha,beta,0)00(-beta,alpha,0)00, while the structures of all tungstates are (3 + 1)D incommensurately modulated with superspace group I2/b(alpha beta 0)00. In both cases the modulation arises because of cation-vacancy ordering at the A site. The prominent structural motif is formed by columns of A-site vacancies running along the c-axis. These vacant columns occur in rows of two or three aligned along the [110] direction of the scheelite subcell. The replacement of the smaller Gd3+ by the larger Eu3+ at the A-sublattice does not affect the nature of the incommensurate modulation, but an increasing replacement of Mo6+ by W6+ switches the modulation from (3 + 2)D to (3 + 1)D regime. Thus, these solid solutions can be considered as a model system where the incommensurate modulation can be monitored as a function of cation nature while the number of cation vacancies at the A sites remain constant upon the isovalent cation replacement. All compounds' luminescent properties were measured, and the optical properties were related to the structural properties of the materials. CaGd2(1-x)(MoO4)(4(1-y))(WO4)(4y) phosphors emit intense red light dominated by the D-5(0)-F-7(2) transition at 612 nm, along with other transitions from the D-5(1) and D-5(0) excited states. The intensity of the 5D0-7F2 transition reaches a maximum at x = 0.5 for y = 0 and 1. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000327045000030 |
Publication Date |
2013-09-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
63 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2013 IF: 8.535 |
Call Number |
UA @ lucian @ c:irua:112776 |
Serial |
1594 |
Permanent link to this record |
|
|
|
Author |
Mikita, R.; Aharen, T.; Yamamoto, T.; Takeiri, F.; Ya, T.; Yoshimune, W.; Fujita, K.; Yoshida, S.; Tanaka, K.; Batuk, D.; Abakumov, A.M.; Brown, C.M.; Kobayashi, Y.; Kageyama, H.; |
Title |
Topochemical nitridation with anion vacancy -assisted N3-/O2- exchange |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
138 |
Issue |
138 |
Pages |
3211-3217 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We present how the introduction of anion vacancies in oxyhydrides enables a route to access new oxynitrides, by conducting ammonolysis of perovskite oxyhydride EuTiO3-xHx (x similar to 0.18). At 400 degrees C, similar to our studies on BaTiO3-xHx, hydride lability enables a low temperature direct ammonolysis of EUTi3.82+O-2.82/H-0.18, leading to the N3-/H--exchanged product EuTi4+O2.82No0.12 square 0.06 center dot When the ammonolysis temperature was increased up to 800 degrees C, we observed a further nitridation involving N3-/O2- exchange, yielding a fully oxidized Eu3+Ti4+O2N with the GdFeO3-type distortion (Pnma) as a metastable phase, instead of pyrochlore structure. Interestingly, the same reactions using the oxide EuTiO3 proceeded through a 1:1 exchange of N3- with O-2 only above 600 degrees C and resulted in incomplete nitridation to EuTi02.25N0.75, indicating that anion vacancies created during the initial nitridation process of EuTiO2.82H0.18 play a crucial role in promoting anion (N3-/O2-) exchange at high temperatures. Hence, by using (hydride-induced) anion-deficient precursors, we should be able to expand the accessible anion composition of perovskite oxynitrides. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000371945800055 |
Publication Date |
2016-02-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.858 |
Call Number |
UA @ lucian @ c:irua:133156 |
Serial |
4266 |
Permanent link to this record |
|
|
|
Author |
Mikhailova, D.; Reichel, P.; Tsirlin, A.A.; Abakumov, A.M.; Senyshyn, A.; Mogare, K.M.; Schmidt, M.; Kuo, C.Y.; Pao, C.W.; Pi, T.W.; Lee, J.F.; Hu, Z.; Tjeng, L.H.; |
Title |
Oxygen-driven competition between low-dimensional structures of Sr3CoMO6 and Sr3CoMO7-\delta with M = Ru,Ir |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
43 |
Issue |
37 |
Pages |
13883-13891 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have realized a reversible structure transformation of one-dimensional 1D K4CdCl6-type Sr3CoMO6 with the Co2+/M4+ cation ordering into the two-dimensional 2D double layered Ruddlesden-Popper structure Sr3CoMO7-delta with a random distribution of Co and M (with M = Ru, Ir) upon increasing the partial oxygen pressure. The combined soft and hard X-ray absorption spectroscopy studies show that under transformation, Co and M cations were oxidized to Co3+ and M5+. During oxidation, high-spin Co2+ in Sr3CoMO6 first transforms into high-spin Co3+ in oxygen-deficient Sr3CoMO7-delta, and then further transforms into low-spin Co3+ in fully oxidized Sr3CoMO7 upon further increasing the partial pressure of oxygen. The 1D Sr3CoMO6 compound is magnetically ordered at low temperatures with the magnetic moments lying along the c-axis. Their alignment is parallel for Sr3CoRuO6 and antiparallel for Sr3CoIrO6. The 2D compounds reveal a spin-glass-like behavior related to the random distribution of magnetic cations in the structure. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000342074100009 |
Publication Date |
2014-07-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.029; 2014 IF: 4.197 |
Call Number |
UA @ lucian @ c:irua:119960 |
Serial |
2545 |
Permanent link to this record |
|
|
|
Author |
McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.; |
Title |
Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the electrochemical society |
Abbreviated Journal |
J Electrochem Soc |
Volume |
162 |
Issue |
162 |
Pages |
A1341-A1351 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000355643700030 |
Publication Date |
2015-04-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0013-4651;1945-7111; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.259 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.259; 2015 IF: 3.266 |
Call Number |
c:irua:126445 |
Serial |
2903 |
Permanent link to this record |
|
|
|
Author |
Marikutsa, A.V.; Rumyantseva, M.N.; Frolov, D.D.; Morozov, I.V.; Boltalin, A.I.; Fedorova, A.A.; Petukhov, I.A.; Yashina, L.V.; Konstantinova, E.A.; Sadovskaya, E.M.; Abakumov, A.M.; Zubavichus, Y.V.; Gaskov, A.M.; |
Title |
Role of PdOx and RuOy clusters in oxygen exchange between nanocrystalline tin dioxide and the gas phase |
Type |
A1 Journal article |
Year |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
117 |
Issue |
45 |
Pages |
23858-23867 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of palladium- and ruthenium-based clusters on nanocrystalline tin dioxide interaction with oxygen was studied by temperature-programmed oxygen isotopic exchange with mass-spectrometry detection. The modification of aqueous sol-gel prepared SnO2 by palladium and, to a larger extent, by ruthenium, increases surface oxygen concentration on the materials. The revealed effects on oxygen exchange-lowering the threshold temperature, separation of surface oxygen contribution to the process, increase of heteroexchange rate and oxygen diffusion coefficient, decrease of activation energies of exchange and diffusion-were more intensive for Ru-modified SnO2 than in the case of SnO2/Pd. The superior promoting activity of ruthenium on tin dioxide interaction with oxygen was interpreted by favoring the dissociative O-2 adsorption and increasing the oxygen mobility, taking into account the structure and chemical composition of the modifier clusters. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000327110500046 |
Publication Date |
2013-10-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
20 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
Call Number |
UA @ lucian @ c:irua:112706 |
Serial |
2924 |
Permanent link to this record |
|
|
|
Author |
Li, M.R.; Adem, U.; McMitchell, S.R.C.; Xu, Z.; Thomas, C.I.; Warren, J.E.; Giap, D.V.; Niu, H.; Wan, X.; Palgrave, R.G.; Schiffmann, F.; Cora, F.; Slater, B.; Burnett, T.L.; Cain, M.G.; Abakumov, A.M.; Van Tendeloo, G.; Thomas, M.F.; Rosseinsky, M.J.; Claridge, J.B.; |
Title |
A polar corundum oxide displaying weak ferromagnetism at room temperature |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
134 |
Issue |
8 |
Pages |
3737-3747 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO3 (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO3 has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO3. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000301161600027 |
Publication Date |
2012-01-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
48 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
Call Number |
UA @ lucian @ c:irua:97200 |
Serial |
2658 |
Permanent link to this record |
|
|
|
Author |
Gou, H.; Tsirlin, A.A.; Bykova, E.; Abakumov, A.M.; Van Tendeloo, G.; Richter, A.; Ovsyannikov, S.V.; Kurnosov, A.V.; Trots, D.M.; Konôpková, Z.; Liermann, H.P.; Dubrovinsky, L.; Dubrovinskaia, N.; |
Title |
Peierls distortion, magnetism, and high hardness of manganese tetraboride |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
89 |
Issue |
6 |
Pages |
064108-64109 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report crystal structure, electronic structure, and magnetism of manganese tetraboride, MnB4, synthesized under high-pressure, high-temperature conditions. In contrast to superconducting FeB4 and metallic CrB4, which are both orthorhombic, MnB4 features a monoclinic crystal structure. Its lower symmetry originates from a Peierls distortion of the Mn chains. This distortion nearly opens the gap at the Fermi level, but despite the strong dimerization and the proximity of MnB4 to the insulating state, we find indications for a sizable paramagnetic effective moment of about 1.7 mu(B)/f.u., ferromagnetic spin correlations, and, even more surprisingly, a prominent electronic contribution to the specific heat. However, no magnetic order has been observed in standard thermodynamic measurements down to 2 K. Altogether, this renders MnB4 a structurally simple but microscopically enigmatic material; we argue that its properties may be influenced by electronic correlations. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000332405000002 |
Publication Date |
2014-02-24 |
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 |
39 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2014 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:115819 |
Serial |
2571 |
Permanent link to this record |
|
|
|
Author |
Gou, H.; Dubrovinskaia, N.; Bykova, E.; Tsirlin, A.A.; Kasinathan, D.; Schnelle, W.; Richter, A.; Merlini, M.; Hanfland, M.; Abakumov, A.M.; Batuk, D.; Van Tendeloo, G.; Nakajima, Y.; Kolmogorov, A.N.; Dubrovinsky, L.; |
Title |
Discovery of a superhard iron tetraboride superconductor |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
111 |
Issue |
15 |
Pages |
157002-157005 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Single crystals of novel orthorhombic (space group Pnnm) iron tetraboride FeB4 were synthesized at pressures above 8 GPa and high temperatures. Magnetic susceptibility and heat capacity measurements demonstrate bulk superconductivity below 2.9 K. The putative isotope effect on the superconducting critical temperature and the analysis of specific heat data indicate that the superconductivity in FeB4 is likely phonon mediated, which is rare for Fe-based superconductors. The discovered iron tetraboride is highly incompressible and has the nanoindentation hardness of 62(5) GPa; thus, it opens a new class of highly desirable materials combining advanced mechanical properties and superconductivity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000325371500011 |
Publication Date |
2013-10-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
127 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
Call Number |
UA @ lucian @ c:irua:110820 |
Serial |
729 |
Permanent link to this record |
|
|
|
Author |
Chernov, S.V.; Dobrovolsky, Y.A.; Istomin, S.Y.; Antipov, E.V.; Grins, J.; Svensson, G.; Tarakina, N.V.; Abakumov, A.M.; Van Tendeloo, G.; Eriksson, S.G.; Rahman, S.M.H.; |
Title |
_Sr{2}GaScO5, Sr10Ga6Sc4O25, and SrGa0.75Sc0.25O2.5 : a play in the octahedra to tetrahedra ratio in oxygen-deficient perovskites |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
51 |
Issue |
2 |
Pages |
1094-1103 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Three different perovskite-related phases were isolated in the SrGa(1-x)Sc(x)O(2.5) system: Sr(2)GaScO(5), Sr(10)Ga(6)Sc(4)O(25), and SrGa(0.75)Sc(0.25)O(2.5), Sr(2)GaScO(5) (x = 0.5) crystallizes in a brownrnillerite-type structure [space group (S.G.) Icmm, a = 5.91048(5) angstrom, b = 15.1594(1) angstrom, and c = 5.70926(4) angstrom] with complete ordering of Sc(3+) and Ga(3+) over octahedral and tetrahedral positions, respectively. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) (x = 0.4) was determined by the Monte Carlo method and refined using a combination of X-ray, neutron, and electron diffraction data [S.G. I4(1)/a, a = 17.517(1) angstrom, c = 32.830(3) angstrom]. It represents a novel type of ordering of the B cations and oxygen vacancies in perovskites. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) can be described as a stacking of eight perovskite layers along the c axis ...[-(Sc/Ga)O(1.6)-SrO(0.8)-(Sc/Ga)O(1.8)-SrO(0.8)-](2 center dot center dot center dot) Similar to Sr(2)GaScO(5), this structure features a complete ordering of the Sc(3+) and Ga(3+) cations over octahedral and tetrahedral positions, respectively, within each layer. A specific feature of the crystal structure of Sr(10)Ga(6)Sc(4)O(25) is that one-third of the tetrahedra have one vertex not connected with other Sc/Ga cations. Further partial replacement of Sc(3+) by Ga(3+) leads to the formation of the cubic perovskite phase SrGa(0.75)Sc(0.25)O(2.5) (x = 0.25) with a = 3.9817(4) angstrom. This compound incorporates water molecules in the structure forming SrGa(0.75)Sc(0.25)O(2.5)center dot xH(2)O hydrate, which exhibits a proton conductivity of similar to 2.0 x 10(-6) S/cm at 673 K. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000299028800042 |
Publication Date |
2011-12-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
Call Number |
UA @ lucian @ c:irua:96229 |
Serial |
3559 |
Permanent link to this record |
|
|
|
Author |
Charkin, D.O.; Urmanov, A.V.; Kazakov, S.M.; Batuk, D.; Abakumov, A.M.; Knöner, S.; Gati, E.; Wolf, B.; Lang, M.; Shevelkov, A.V.; Van Tendeloo, G.; Antipov, E.V.; |
Title |
Synthesis, crystal structure, transport, and magnetic properties of novel ternary copper phosphides, A2Cu6P5(A = Sr, Eu) and EuCu4P3 |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
51 |
Issue |
16 |
Pages |
8948-8955 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6P5 and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure, while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K <= T <= 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at T-C = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000307606200042 |
Publication Date |
2012-07-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
Call Number |
UA @ lucian @ c:irua:102217 |
Serial |
3453 |
Permanent link to this record |
|
|
|
Author |
Charkin, D.O.; Demchyna, R.; Prots, Y.; Borrmann, H.; Burkhardt, U.; Schwarz, U.; Schnelle, W.; Plokhikh, I.V.; Kazakov, S.M.; Abakumov, A.M.; Batuk, D.; Verchenko, V.Y.; Tsirlin, A.A.; Curfs, C.; Grin, Y.; Shevelkov, A.V.; |
Title |
Two New Arsenides, Eu7Cu44As23 and Sr7Cu44As23, With a New Filled Variety of the BaHg11 Structure |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
53 |
Issue |
20 |
Pages |
11173-11184 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Two new ternary arsenides, namely, Eu7Cu44As23 and Sr7Cu44As23, were synthesized from elements at 800 degrees C. Their crystal structure represents a new filled version of the BaHg11 motif with cubic voids alternately occupied by Eu(Sr) and As atoms, resulting in a 2 x 2 x 2 superstructure of the aristotype: space group Fm (3) over barm, a = 16.6707(2) angstrom and 16.7467(2) angstrom, respectively. The Eu derivative exhibits ferromagnetic ordering below 17.5 K. In agreement with band structure calculations both compounds are metals, exhibiting relatively low thermopower, but high electrical and low thermal conductivity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000343527700049 |
Publication Date |
2014-09-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2014 IF: 4.762 |
Call Number |
UA @ lucian @ c:irua:121141 |
Serial |
3784 |
Permanent link to this record |
|
|
|
Author |
Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.; |
Title |
Evidence of oxygen-dependent modulation in LuFe2O4 |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
6 |
Pages |
064102-064120,10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000299896900003 |
Publication Date |
2012-02-06 |
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 |
Hercules |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:95042 |
Serial |
1095 |
Permanent link to this record |
|
|
|
Author |
Blandy, J.N.; Abakumov, A.M.; Christensen, K.E.; Hadermann, J.; Adamson, P.; Cassidy, S.J.; Ramos, S.; Free, D.G.; Cohen, H.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J.; |
Title |
Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide |
Type |
A1 Journal article |
Year |
2015 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
Volume |
3 |
Issue |
3 |
Pages |
041520 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000353828400027 |
Publication Date |
2015-04-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2166-532X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.335 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.335; 2015 IF: NA |
Call Number |
c:irua:126021 |
Serial |
3049 |
Permanent link to this record |
|
|
|
Author |
Abakumov, M.A.; Nukolova, N.V.; Sokolsky-Papkov, M.; Shein, S.A.; Sandalova, T.O.; Vishwasrao, H.M.; Grinenko, N.F.; Gubsky, I.L.; Abakumov, A.M.; Kabanov, A.V.; Chekhonin, V.P.; |
Title |
VEGF-targeted magnetic nanoparticles for MRI visualization of brain tumor |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanomedicine: nanotechnology, biology and medicine |
Abbreviated Journal |
Nanomed-Nanotechnol |
Volume |
11 |
Issue |
11 |
Pages |
825-833 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
This work is focused on synthesis and characterization of targeted magnetic nanoparticles as magnetic resonance imaging (MRI) agents for in vivo visualization of gliomas. Ferric oxide (Fe3O4) cores were synthesized by thermal decomposition and coated with bovine serum albumin (BSA) to form nanoparticles with D-eff of 53 +/- 9 nm. The BSA was further cross-linked to improve colloidal stability. Monoclonal antibodies against vascular endothelial growth factor (mAbVEGF) were covalently conjugated to BSA through a polyethyleneglycol linker. Here we demonstrate that 1) BSA coated nanoparticles are stable and non-toxic to different cells at concentration up to 2.5 mg/mL; 2) conjugation of monoclonal antibodies to nanoparticles promotes their binding to VEGF-positive glioma C6 cells in vitro; 3) targeted nanoparticles are effective in MRI visualization of the intracranial glioma. Thus, mAbVEGF-targeted BSA-coated magnetic nanoparticles are promising MRI contrast agents for glioma visualization. (C) 2015 Elsevier Inc. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000354559600004 |
Publication Date |
2015-01-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1549-9634; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.72 |
Times cited |
62 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 5.72; 2015 IF: 6.155 |
Call Number |
c:irua:126351 |
Serial |
3838 |
Permanent link to this record |
|
|
|
Author |
Abakumov, A.M.; Batuk, M.; Tsirlin, A.A.; Tyablikov, O.A.; Sheptyakov, D.V.; Filimonov, D.S.; Pokholok, K.V.; Zhidal, V.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; |
Title |
Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
52 |
Issue |
14 |
Pages |
7834-7843 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000322087100006 |
Publication Date |
2013-02-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
10 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
Call Number |
UA @ lucian @ c:irua:109213 |
Serial |
3196 |
Permanent link to this record |