Theoretical study on the second hyperpolarizabilities of tetrathiafulvalene (TTF) and tetrathiapentalene (TTP) using highly correlated ab initio MO and the density functional theory methods

An ab initio study of the structural, elastic and vibrational properties of the lutetium gallium garnet (Lu3Ga5O12) under pressure has been performed in the framework of the density functional theory, up to 95 GPa.

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A theoretical study of α- and β-d-glucopyranose conformations by the density functional theory

Chemical Physics Letters ◽

10.1016/j.cplett.2005.11.113 ◽

2006 ◽

Vol 419 (4-6) ◽

pp. 326-332 ◽

Cited By ~ 30

Author(s):

Nobuaki Miura ◽

Tohru Taniguchi ◽

Kenji Monde ◽

Shin-Ichiro Nishimura

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Theoretical Study ◽

Functional Theory ◽

The Density Functional Theory

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Mechanisms of Diffusion and Dissociation of E-Centers in Silicon

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.237-240.1129 ◽

2005 ◽

Vol 237-240 ◽

pp. 1129-1134

Author(s):

Mariya G. Ganchenkova ◽

V.A. Borodin ◽

Risto M. Nieminen

Keyword(s):

Density Functional Theory ◽

Monte Carlo ◽

Ab Initio Calculations ◽

Ab Initio ◽

Density Functional ◽

Kinetic Monte Carlo ◽

Binding Energies ◽

Functional Theory ◽

The Density Functional Theory ◽

Charge States

In this paper we discuss possible mechanisms of PV annealing in Si. Our approach includes a combination of density functional theory and lattice kinetic Monte-Carlo (LKMC) simulations. The density functional theory is used to find the binding energies and jump barriers for P-V pair at different separations (from one to three interatomic bonds between complex constituents) and in different charge states. The mobility of the complex is simulated by LKMC with event probabilities calculated based on the energies from ab-initio calculations. .

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Substantial Variations in the Optical Absorption and Reflectivity of Graphene When the Concentrations of Vacancies and Doping with Fluorine, Nitrogen, and Oxygen Change

International Journal of Molecular Sciences ◽

10.3390/ijms22136832 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6832

Author(s):

Ali Fransuani Jiménez-González ◽

Juan Manuel Ramírez-de-Arellano ◽

Luis Fernando Magaña

Keyword(s):

Density Functional Theory ◽

Optical Absorption ◽

Band Structure ◽

Numerical Simulations ◽

Ab Initio ◽

Density Functional ◽

Functional Theory ◽

The Density Functional Theory ◽

Density Values

We performed ab initio numerical simulations with the density functional theory to investigate the variations in the band structure, optical absorption, and the reflectivity of vacancy-graphene doped with nitrogen, oxygen, and fluorine for different densities. We considered the density values 0.78%, 1.02%, 1.39%, 2.00%, 3.12%, 5.55%, and 12.5% for the vacancies and doping. In the infrared and visible ranges for all cases, vacancies included, there is a substantial increment in the absorption and reflectivity concerning graphene. The most significant changes are for fluorine and oxygen at a concentration of 12.5%.

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DFT analysis of crystal polarity on graphene surface

Journal of Physics Conference Series ◽

10.1088/1742-6596/2015/1/012105 ◽

2021 ◽

Vol 2015 (1) ◽

pp. 012105

Author(s):

Alexander Pavlov ◽

Alexey Mozharov ◽

Yury Berdnikov ◽

Camille Barbier ◽

Jean-Christophe Harmand ◽

...

Keyword(s):

Density Functional Theory ◽

Ab Initio ◽

Density Functional ◽

Optoelectronic Device ◽

Device Design ◽

Theory Analysis ◽

Functional Theory ◽

Graphene Surface ◽

Gan Nanowires ◽

The Density Functional Theory

Abstract We report an ab-initio study of the preferred polarity for wurtzite GaN nanostructures on virtual graphene substrates. By means of the density functional theory analysis we show that N-polar nanostructures on graphene are energetically favorable in comparison to Ga-polar. These finding are in agreement with experimentally observed N-polarity of wurtzite GaN nanowires grown on graphene substrate. We believe that the revealed polarity preference is of importance for piezoelectric and optoelectronic device design.

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Does Osmium Carbide Exist? Ab initio Investigation

MRS Proceedings ◽

10.1557/proc-987-0987-pp01-07 ◽

2006 ◽

Vol 987 ◽

Author(s):

M. Zemzemi ◽

M. Hebbache ◽

D. Zivkovic ◽

L Stuparevic

Keyword(s):

Mechanical Properties ◽

Density Functional Theory ◽

Transition Metals ◽

Ab Initio ◽

Density Functional ◽

Ambient Pressure ◽

Hexagonal Structure ◽

Functional Theory ◽

The Density Functional Theory ◽

Good Agreement

AbstractTransition metals of the platinum group (Os, Ir, Pt, Ru, Re, Rh) do not form carbides and nitrides at ambient pressure. Osmium carbide seems to have been synthesized at zero pressure by Kempter and Nadler forty six years ago. According to the authors, OsC crystallizes in WC-type structure and has a hardness equal to 2000 kg mm-2. Up to date, no other experimental confirmation is available. We studied the electronic and mechanical properties of this hypothetical carbide using an approach based on the density-functional theory. We found that the work of the above mentioned authors is sound. The calculated lattice parameters are in good agreement with that given by those authors and a rough estimate also showed that the hardness given by them is reasonable. However, we found that the hexagonal structure of osmium carbide is electronically and mechanically unstable.

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What Differs on the Enzymatic Acetylation Mechanisms for Arylamines and Arylhydrazines Substrates? A Theoretical Study

Research Letters in Biochemistry ◽

10.1155/2009/783035 ◽

2009 ◽

Vol 2009 ◽

pp. 1-5

Author(s):

Qing-An Qiao ◽

Xiao-Min Sun ◽

Jie Jing ◽

Xin Chen ◽

Hua-Yang Wang ◽

...

Keyword(s):

Experimental Data ◽

Density Functional Theory ◽

Density Functional ◽

Theoretical Study ◽

Transition States ◽

Ring Structure ◽

Membered Ring ◽

Functional Theory ◽

Lone Pairs ◽

The Density Functional Theory

The acetylation mechanisms of several selected typical substrates from experiments, including arylamines and arylhydrazines, are investigated with the density functional theory in this paper. The results indicate that all the transition states are characterized by a four-membered ring structure, and hydralazine (HDZ) is the most potent substrate. The bioactivity for all the compounds is increased in a sequence ofPABA≈4-AS<4-MA<5-AS≈INH<HDZ. The conjunction effect and the delocalization of the lone pairs of N atom play a key role in the reaction. All the results are consistent with the experimental data.

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