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Author | Tit, N.; Al Ezzi, M.M.; Abdullah, H.M.; Yusupov, M.; Kouser, S.; Bahlouli, H.; Yamani, Z.H. | ||||
Title | Detection of CO2 using CNT-based sensors: Role of Fe catalyst on sensitivity and selectivity | Type | A1 Journal article | ||
Year | 2017 | Publication | Materials chemistry and physics | Abbreviated Journal | Mater Chem Phys |
Volume | 186 | Issue | 186 | Pages | 353-364 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The adsorption of CO2 on surfaces of graphene and carbon nanotubes (CNTs), decorated with Fe atoms, are investigated using the self-consistent-charge density-functional tight-binding (SCC-DFTB) method, neglecting the heat effects. Fe ad-atoms are more stable when they are dispersed on hollow sites. They introduce a large density of states at the Fermi level (N-F); where keeping such density low would help in gas sensing. Furthermore, the Fe ad-atom can weaken the C=O double bonds of the chemisorbed CO2 molecule, paving the way for oxygen atoms to drain more charges from Fe. Consequently, chemisorption of CO2 molecules reduces both N-F and the conductance while it enhances the sensitivity with the increasing gas dose. Conducting armchair CNTs (ac-CNTs) have higher sensitivity than graphene and semiconducting zigzag CNTs (zz-CNT5). Comparative study of sensitivity of ac-CNT-Fe composite towards various gases (e.g., O-2, N-2, H-2, H2O, CO and CO2) has shown high sensitivity and selectivity towards CO, CO2 and H2O gases. (C) 2016 Elsevier B.V. All rights reserved. | ||||
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Publisher | Place of Publication | Lausanne | Editor | ||
Language | Wos | 000390621200044 | Publication Date | 2016-11-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0254-0584 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.084 | Times cited | 17 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.084 | |||
Call Number | UA @ lucian @ c:irua:140333 | Serial | 4465 | ||
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Author | Mees, M.J.; Pourtois, G.; Rosciano, F.; Put, B.; Vereecken, P.M.; Stesmans, A. | ||||
Title | First-principles material modeling of solid-state electrolytes with the spinel structure | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | Issue | Pages | |||
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Ionic diffusion through the novel (AlxMg1-2xLix)Al2O4 spinel electrolyte is investigated using first-principles calculations, combined with the Kinetic Monte Carlo algorithm. We observe that the ionic diffusion increases with the lithium content x. Furthermore, the structural parameters, formation enthalpies and electronic structures of (AlxMg1-2xLix)Al2O4 are calculated for various stoichiometries. The overall results indicate the (AlxMg1-2xLix)Al2O4 stoichiometries x = 0.2...0.3 as most promising. The (AlxMg1-2xLix)Al2O4 electrolyte is a potential candidate for the all-spinel solid-state battery stack, with the material epitaxially grown between well-known spinel electrodes, such as LiyMn2O4 and Li4+3yTi5O12 (y = 0...1). Due to their identical crystal structure, a good electrolyte-electrode interface is expected. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000332395700048 | Publication Date | 2014-02-07 | |
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 | 8 | Open Access | |
Notes | Approved | Most recent IF: 4.123; 2014 IF: 4.493 | |||
Call Number | UA @ lucian @ c:irua:128893 | Serial | 4520 | ||
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Author | Shirazi, M.; Bogaerts, A.; Neyts, E.C. | ||||
Title | A DFT study of H-dissolution into the bulk of a crystalline Ni(111) surface: a chemical identifier for the reaction kinetics | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 19 | Issue | 19 | Pages | 19150-19158 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this study, we investigated the diffusion of H-atoms to the subsurface and their further diffusion into the bulk of a Ni(111) crystal by means of density functional theory calculations in the context of thermal and plasma-assisted catalysis. The H-atoms at the surface can originate from the dissociative adsorption of H2 or CH4 molecules, determining the surface H-coverage. When a threshold H-coverage is passed, corresponding to 1.00 ML for the crystalline Ni(111) surface, the surface-bound H-atoms start to diffuse to the subsurface. A similar threshold coverage is observed for the interstitial H-coverage. Once the interstitial sites are filled up with a coverage above 1.00 ML of H, dissolution of interstitial H-atoms to the layer below the interstitial sites will be initiated. Hence, by applying a high pressure or inducing a reactive plasma and high temperature, increasing the H-flux to the surface, a large amount of hydrogen can diffuse in a crystalline metal like Ni and can be absorbed. The formation of metal hydride may modify the entire reaction kinetics of the system. Equivalently, the H-atoms in the bulk can easily go back to the surface and release a large amount of heat. In a plasma process, H-atoms are formed in the plasma, and therefore the energy barrier for dissociative adsorption is dismissed, thus allowing achievement of the threshold coverage without applying a high pressure as in a thermal process. As a result, depending on the crystal plane and type of metal, a large number of H-atoms can be dissolved (absorbed) in the metal catalyst, explaining the high efficiency of plasma-assisted catalytic reactions. Here, the mechanism of H-dissolution is established as a chemical identifier for the investigation of the reaction kinetics of a chemical process. | ||||
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Language | Wos | 000406334300034 | Publication Date | 2017-06-22 | |
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 | 10 | Open Access | OpenAccess |
Notes | Financial support from the Reactive Atmospheric Plasma processIng – eDucation (RAPID) network, through the EU 7th Framework Programme (grant agreement no. 606889), is gratefully acknowledged. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government department (EWI) and the Universiteit Antwerpen. | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @ c:irua:144794 | Serial | 4633 | ||
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Author | Gorbanev, Y.; Verlackt, C.C.W.; Tinck, S.; Tuenter, E.; Foubert, K.; Cos, P.; Bogaerts, A. | ||||
Title | Combining experimental and modelling approaches to study the sources of reactive species induced in water by the COST RF plasma jet | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 20 | Issue | 4 | Pages | 2797-2808 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The vast biomedical potential of cold atmospheric pressure plasmas (CAPs) is governed by the formation of reactive species. These biologically active species are formed upon the interaction of CAPs with the surroundings. In biological milieu, water plays an essential role. The development of biomedical CAPs thus requires understanding of the sources of the reactive species in aqueous media exposed to the plasma. This is especially important in case of the COST RF plasma jet, which is developed as a reference microplasma system. In this work, we investigated the formation of the OH radicals, H atoms and H2O2 in aqueous solutions exposed to the COST plasma jet. This was done by combining experimental and modelling approaches. The liquid phase species were analysed using UV-Vis spectroscopy and spin trapping with hydrogen isotopes and electron paramagnetic resonance (EPR) spectroscopy. The discrimination between the species formed from the liquid phase and the gas phase molecules was performed by EPR and 1H-NMR analyses of the liquid samples. The concentrations of the reactive species in the gas phase plasma were obtained using a zero-dimensional (0D) chemical kinetics computational model. A three-dimensional (3D) fluid dynamics model was developed to provide information on the induced humidity in the plasma effluent. The comparison of the experimentally obtained trends for the formation of the species as a function of the feed gas and effluent humidity with the modelling results suggest that all reactive species detected in our system are mostly formed in the gas phase plasma inside the COST jet, with minor amounts arising from the plasma effluent humidity. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000423505500066 | Publication Date | 2018-01-05 | |
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 | 23 | Open Access | OpenAccess |
Notes | We are grateful to Volker Schulz-von der Gathen (Experimental Physics II: Application Oriented Plasma Physics, Ruhr-Universita¨t Bochum, Germany) for providing the COST RF plasma jet. We thank our colleagues at the University of Antwerp: Gilles Van Loon (Mechanical Workshop), Karen Leyssens (Research group PLASMANT), and Sylvia Dewilde (Department of Biomedical Sciences) for their help with the equipment. This work was funded by the European Marie Sklodowska-Curie Individual Fellowship ‘LTPAM’ within Horizon2020 (grant no. 657304). Stefan Tinck thanks the Fund for Scientific Research – Flanders (FWO) for supporting his work (grant no. 0880.212.840). | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @c:irua:148365 | Serial | 4808 | ||
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Author | Verlackt, C.C.W.; Van Boxem, W.; Bogaerts, A. | ||||
Title | Transport and accumulation of plasma generated species in aqueous solution | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 20 | Issue | 10 | Pages | 6845-6859 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The interaction between cold atmospheric pressure plasma and liquids is receiving increasing attention for various applications. In particular, the use of plasma-treated liquids (PTL) for biomedical applications is of growing importance, in particular for sterilization and cancer treatment. However, insight into the underlying mechanisms of plasma–liquid interactions is still scarce. Here, we present a 2D fluid dynamics model for the interaction between a plasma jet and liquid water. Our results indicate that the formed reactive species originate from either the gas phase (with further solvation) or are formed at the liquid interface. A clear increase in the aqueous density of H2O2, HNO2/NO2- and NO3- is observed as a function of time, while the densities of O3, HO2/O2- and ONOOH/ONOO- are found to quickly reach a maximum due to chemical reactions in solution. The trends observed in our model correlate well with experimental observations from the literature. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000429286100009 | Publication Date | 2018-02-06 | |
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 | 35 | Open Access | OpenAccess |
Notes | The authors thank Petr Luke`s (Institute of Plasma Physics AS CR, Czech Republic) and Yury Gorbanev (UAntwerp, group PLASMANT) for the fruitful discussions regarding the chemistry in the model and the plasma–liquid interactions. | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @c:irua:149557 | Serial | 4908 | ||
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Author | Bal, K.M.; Neyts, E.C. | ||||
Title | Modelling molecular adsorption on charged or polarized surfaces: a critical flaw in common approaches | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 20 | Issue | 13 | Pages | 8456-8459 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | A number of recent computational material design studies based on density functional theory (DFT) calculations have put forward a new class of materials with electrically switchable chemical characteristics that can be exploited in the development of tunable gas storage and electrocatalytic applications. We find systematic flaws in almost every computational study of gas adsorption on polarized or charged surfaces, stemming from an improper and unreproducible treatment of periodicity, leading to very large errors of up to 3 eV in some cases. Two simple corrective procedures that lead to consistent results are proposed, constituting a crucial course correction to the research in the field. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000428779700007 | Publication Date | 2018-03-12 | |
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 | 8 | Open Access | OpenAccess |
Notes | K. M. B. is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation – Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government – department EWI. | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @c:irua:150357 | Serial | 4916 | ||
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Author | Gorbanev, Y.; Van der Paal, J.; Van Boxem, W.; Dewilde, S.; Bogaerts, A. | ||||
Title | Reaction of chloride anion with atomic oxygen in aqueous solutions: can cold plasma help in chemistry research? | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 21 | Issue | 8 | Pages | 4117-4121 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Cold atmospheric plasma in contact with solutions has many applications, but its chemistry contains many unknowns such as the undescribed reactions with solutes. By combining experiments and modelling, we report the first direct demonstration of the reaction of chloride with oxygen atoms in aqueous solutions exposed to cold plasma. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000461722500001 | Publication Date | 2019-01-30 | |
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 | 4 | Open Access | Not_Open_Access: Available from 31.01.2020 |
Notes | H2020 Marie Skłodowska-Curie Actions, 743151 ; Fonds Wetenschappelijk Onderzoek, 11U5416N ; | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @UA @ admin @ c:irua:157688 | Serial | 5167 | ||
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Author | Dabral, A.; Lu, A.K.A.; Chiappe, D.; Houssa, M.; Pourtois, G. | ||||
Title | A systematic study of various 2D materials in the light of defect formation and oxidation | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 21 | Issue | 3 | Pages | 1089-1099 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The thermodynamic aspects of various 2D materials are explored using Density Functional Theory (DFT). Various metal chalcogenides (MX2, M = metal, chalcogen X = S, Se, Te) are investigated with respect to their interaction and stability under different ambient conditions met in the integration process of a transistor device. Their interaction with high- dielectrics is also addressed, in order to assess their possible integration in Complementary Metal Oxide Semiconductor (CMOS) field effect transistors. 2D materials show promise for high performance nanoelectronic devices, but the presence of defects (vacancies, grain boundaries,...) can significantly impact their electronic properties. To assess the impact of defects, their enthalpies of formation and their signature levels in the density of states have been studied. We find, consistently with literature reports, that chalcogen vacancies are the most likely source of defects. It is shown that while pristine 2D materials are in general stable whenever set in contact with different ambient atmospheres, the presence of defective sites affects the electronic properties of the 2D materials to varying degrees. We observe that all the 2D materials studied in the present work show strong reactivity towards radical oxygen plasma treatments while reactivity towards other common gas phase chemical such as O-2 and H2O and groups present at the high- surface varies significantly between species. While energy band-gaps, effective masses and contact resistivities are key criteria in selection of 2D materials for scaled CMOS and tunneling based devices, the phase and ambient stabilities might also play a very important role in the development of reliable nanoelectronic applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000456147000009 | Publication Date | 2018-12-19 | |
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 | 1 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 4.123 | |||
Call Number | UA @ admin @ c:irua:156715 | Serial | 5267 | ||
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Author | Van der Paal, J.; Hong, S.-H.; Yusupov, M.; Gaur, N.; Oh, J.-S.; Short, R.D.; Szili, E.J.; Bogaerts, A. | ||||
Title | How membrane lipids influence plasma delivery of reactive oxygen species into cells and subsequent DNA damage : an experimental and computational study | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 21 | Issue | 35 | Pages | 19327-19341 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The mechanisms of plasma in medicine are broadly attributed to plasma-derived reactive oxygen and nitrogen species (RONS). In order to exert any intracellular effects, these plasma-derived RONS must first traverse a major barrier in the cell membrane. The cell membrane lipid composition, and thereby the magnitude of this barrier, is highly variable between cells depending on type and state (e.g. it is widely accepted that healthy and cancerous cells have different membrane lipid compositions). In this study, we investigate how plasma-derived RONS interactions with lipid membrane components can potentially be exploited in the future for treatment of diseases. We couple phospholipid vesicle experiments, used as simple cell models, with molecular dynamics (MD) simulations of the lipid membrane to provide new insights into how the interplay between phospholipids and cholesterol may influence the response of healthy and diseased cell membranes to plasma-derived RONS. We focus on the (i) lipid tail saturation degree, (ii) lipid head group type, and (iii) membrane cholesterol fraction. Using encapsulated molecular probes, we study the influence of the above membrane components on the ingress of RONS into the vesicles, and subsequent DNA damage. Our results indicate that all of the above membrane components can enhance or suppress RONS uptake, depending on their relative concentration within the membrane. Further, we show that higher RONS uptake into the vesicles does not always correlate with increased DNA damage, which is attributed to ROS reactivity and lifetime. The MD simulations indicate the multifactorial chemical and physical processes at play, including (i) lipid oxidation, (ii) lipid packing, and (iii) lipid rafts formation. The methods and findings presented here provide a platform of knowledge that could be leveraged in the development of therapies relying on the action of plasma, in which the cell membrane and oxidative stress response in cells is targeted. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000486175400045 | Publication Date | 2019-08-21 | |
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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 | 1 | Open Access | |
Notes | Approved | Most recent IF: 4.123 | |||
Call Number | UA @ admin @ c:irua:162782 | Serial | 6303 | ||
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Author | Heirman, P.; Van Boxem, W.; Bogaerts, A. | ||||
Title | Reactivity and stability of plasma-generated oxygen and nitrogen species in buffered water solution: a computational study | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 21 | Issue | 24 | Pages | 12881-12894 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma-treated liquids have great potential for biomedical applications. However, insight into the underlying mechanisms and the exact chemistry is still scarce. In this study, we present the combination of a 0D chemical kinetics and a 2D fluid dynamics model to investigate the plasma treatment of a buffered water solution with the kINPen (R) plasma jet. Using this model, we calculated the gas and liquid flow profiles and the transport and chemistry of all species in the gas and the liquid phase. Moreover, we evaluated the stability of the reactive oxygen and nitrogen species after plasma treatment. We found that of all species, only H2O2, HNO2/NO2-, and HNO3/NO3- are stable in the buffered solution after plasma treatment. This is because both their production and loss processes in the liquid phase are dependent on short-lived radicals (e.g. OH, NO, and NO2). Apart from some discrepancy in the absolute values of the concentrations, which can be explained by the model, all general trends and observations in our model are in qualitative agreement with experimental data and literature. | ||||
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Language | Wos | 000472214000012 | Publication Date | 2019-05-29 | |
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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 | 7 | Open Access | |
Notes | Approved | Most recent IF: 4.123 | |||
Call Number | UA @ admin @ c:irua:161314 | Serial | 6320 | ||
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Author | Bal, K.M.; Fukuhara, S.; Shibuta, Y.; Neyts, E.C. | ||||
Title | Free energy barriers from biased molecular dynamics simulations | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of Chemical Physics | Abbreviated Journal | J Chem Phys |
Volume | 153 | Issue | 11 | Pages | 114118 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Atomistic simulation methods for the quantification of free energies are in wide use. These methods operate by sampling the probability density of a system along a small set of suitable collective variables (CVs), which is, in turn, expressed in the form of a free energy surface (FES). This definition of the FES can capture the relative stability of metastable states but not that of the transition state because the barrier height is not invariant to the choice of CVs. Free energy barriers therefore cannot be consistently computed from the FES. Here, we present a simple approach to calculate the gauge correction necessary to eliminate this inconsistency. Using our procedure, the standard FES as well as its gauge-corrected counterpart can be obtained by reweighing the same simulated trajectory at little additional cost. We apply the method to a number of systems—a particle solvated in a Lennard-Jones fluid, a Diels–Alder reaction, and crystallization of liquid sodium—to demonstrate its ability to produce consistent free energy barriers that correctly capture the kinetics of chemical or physical transformations, and discuss the additional demands it puts on the chosen CVs. Because the FES can be converged at relatively short (sub-ns) time scales, a free energy-based description of reaction kinetics is a particularly attractive option to study chemical processes at more expensive quantum mechanical levels of theory. | ||||
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Language | Wos | 000574665600004 | Publication Date | 2020-09-21 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-9606 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.4 | Times cited | Open Access | ||
Notes | Japan Society for the Promotion of Science, 19H02415 18J22727 ; Fonds Wetenschappelijk Onderzoek, 12ZI420N ; This work was supported, in part, by a Grant-in-Aid for Scientific Research (B) (Grant No. 19H02415) and Grant-in-Aid for a JSPS Research Fellow (Grant No. 18J22727) from the Japan Society for the Promotion of Science (JSPS), Japan. K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation – Flanders), Grant No. 12ZI420N. S.F. was supported by JSPS through the Program for Leading Graduate Schools (MERIT). The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government. The authors are grateful to Pablo Piaggi for making the pair entropy CV code publicly available. | Approved | Most recent IF: 4.4; 2020 IF: 2.965 | ||
Call Number | PLASMANT @ plasmant @c:irua:172456 | Serial | 6420 | ||
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Author | Izadi, M.E.; Bal, K.M.; Maghari, A.; Neyts, E.C. | ||||
Title | Reaction mechanisms of C(3PJ) and C+(2PJ) with benzene in the interstellar medium from quantum mechanical molecular dynamics simulations | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Chemistry Chemical Physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 23 | Issue | 7 | Pages | 4205-4216 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | While spectroscopic data on small hydrocarbons in interstellar media in combination with crossed molecular beam (CMB) experiments have provided a wealth of information on astrochemically relevant species, much of the underlying mechanistic pathways of their formation remain elusive. Therefore, in this work, the chemical reaction mechanisms of C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>and C<sup>+</sup>(<sup>2</sup>P) + C<sub>6</sub>H<sub>6</sub>systems using the quantum mechanical molecular dynamics (QMMD) technique at the PBE0-D3(BJ) level of theory is investigated, mimicking a CMB experiment. Both the dynamics of the reactions as well as the electronic structure for the purpose of the reaction network are evaluated. The method is validated for the first reaction by comparison to the available experimental data. The reaction scheme for the C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system covers the literature data,<italic>e.g.</italic>the major products are the 1,2-didehydrocycloheptatrienyl radical (C<sub>7</sub>H<sub>5</sub>) and benzocyclopropenyl radical (C<sub>6</sub>H<sub>5</sub>–CH), and it reveals the existence of less common pathways for the first time. The chemistry of the C<sup>+</sup>(<sup>2</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system is found to be much richer, and we have found that this is because of more exothermic reactions in this system in comparison to those in the C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system. Moreover, using the QMMD simulation, a number of reaction paths have been revealed that produce three distinct classes of reaction products with different ring sizes. All in all, at all the collision energies and orientations, the major product is the heptagon molecular ion for the ionic system. It is also revealed that the collision orientation has a dominant effect on the reaction products in both systems, while the collision energy mostly affects the charged system. These simulations both prove the applicability of this approach to simulate crossed molecular beams, and provide fundamental information on reactions relevant for the interstellar medium. | ||||
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Language | Wos | 000621595300016 | Publication Date | 2021-01-18 | |
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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 | Open Access | OpenAccess | |
Notes | Fonds Wetenschappelijk Onderzoek, 12ZI420N ; Ministry of Science Research and Technology; Universiteit Antwerpen; The financial support from the Iran Ministry of Science, Research and Technology and PLASMANT Research Group University of Antwerp is highly acknowledged by the authors. K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation – Flanders), Grant 12ZI420N. The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government. | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @c:irua:176672 | Serial | 6742 | ||
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Author | Bal, K.M.; Neyts, E.C. | ||||
Title | Extending and validating bubble nucleation rate predictions in a Lennard-Jones fluid with enhanced sampling methods and transition state theory | Type | A1 Journal article | ||
Year | 2022 | Publication | Journal Of Chemical Physics | Abbreviated Journal | J Chem Phys |
Volume | 157 | Issue | 18 | Pages | 184113-10 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We calculate bubble nucleation rates in a Lennard-Jones fluid through explicit molecular dynamics simulations. Our approach-based on a recent free energy method (dubbed reweighted Jarzynski sampling), transition state theory, and a simple recrossing correction-allows us to probe a fairly wide range of rates in several superheated and cavitation regimes in a consistent manner. Rate predictions from this approach bridge disparate independent literature studies on the same model system. As such, we find that rate predictions based on classical nucleation theory, direct brute force molecular dynamics simulations, and seeding are consistent with our approach and one another. Published rates derived from forward flux sampling simulations are, however, found to be outliers. This study serves two purposes: First, we validate the reliability of common modeling techniques and extrapolation approaches on a paradigmatic problem in materials science and chemical physics. Second, we further test our highly generic recipe for rate calculations, and establish its applicability to nucleation processes. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000885260600002 | Publication Date | 2022-11-14 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-9606 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.4 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.4 | |||
Call Number | UA @ admin @ c:irua:192076 | Serial | 7266 | ||
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Author | Bal, K.M. | ||||
Title | Nucleation rates from small scale atomistic simulations and transition state theory | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Chemical Physics | Abbreviated Journal | J Chem Phys |
Volume | 155 | Issue | 14 | Pages | 144111 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The evaluation of nucleation rates from molecular dynamics trajectories is hampered by the slow nucleation time scale and impact of finite size effects. Here, we show that accurate nucleation rates can be obtained in a very general fashion relying only on the free energy barrier, transition state theory, and a simple dynamical correction for diffusive recrossing. In this setup, the time scale problem is overcome by using enhanced sampling methods, in casu metadynamics, whereas the impact of finite size effects can be naturally circumvented by reconstructing the free energy surface from an appropriate ensemble. Approximations from classical nucleation theory are avoided. We demonstrate the accuracy of the approach by calculating macroscopic rates of droplet nucleation from argon vapor, spanning 16 orders of magnitude and in excellent agreement with literature results, all from simulations of very small (512 atom) systems. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000755502100008 | Publication Date | 2021-09-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9606 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.965 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 2.965 | |||
Call Number | UA @ admin @ c:irua:184937 | Serial | 8320 | ||
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