N–H⋯O versus O–H⋯O: density functional calculation and first principle molecular dynamics study on a quinoline-2-carboxamide N-oxide

A new method for pressure control in first-principle molecular dynamics simulations for finite systems is presented. The extended Lagrangian methodology is applied to generate the equations of motion and the system’s volume is obtained by a purely geometrical procedure, which is inexpensive in terms of computational cost. The implementation of all discussed algorithms was carried out in the program deMon2k where a robust machinery for auxiliary density functional theory calculations exists. The here described methodology extend our effort on property calculations beyond the polyatomic ideal gas approximation on the basis of first-principle electronic structure calculations.

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Anisotropic gap of superconductingCaC6: A first-principles density functional calculation

Physical Review B ◽

10.1103/physrevb.75.020511 ◽

2007 ◽

Vol 75 (2) ◽

Cited By ~ 87

Author(s):

A. Sanna ◽

G. Profeta ◽

A. Floris ◽

A. Marini ◽

E. K. U. Gross ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Density Functional Calculation

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Investigation of Corrosion Inhibitors Adsorption on Metals Using Density Functional Theory and Molecular Dynamics Simulation

Corrosion Inhibitors ◽

10.5772/intechopen.84126 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ambrish Singh ◽

Kashif R. Ansari ◽

Mumtaz A. Quraishi ◽

Yuanhua Lin

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Molecular Dynamics Simulation ◽

Density Functional ◽

Corrosion Inhibitors ◽

Dynamics Simulation ◽

Functional Theory

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Sensitivity of Intra- and Intermolecular Interactions of Benzo[h]quinoline from Car–Parrinello Molecular Dynamics and Electronic Structure Inspection

International Journal of Molecular Sciences ◽

10.3390/ijms22105220 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5220

Author(s):

Jarosław J. Panek ◽

Joanna Zasada ◽

Bartłomiej M. Szyja ◽

Beata Kizior ◽

Aneta Jezierska

Keyword(s):

Molecular Dynamics ◽

Electronic Structure ◽

Hydrogen Bonds ◽

Density Functional ◽

Quantum Effects ◽

Potential Of Mean Force ◽

Probability Density Distribution ◽

Donor And Acceptor ◽

Nuclear Quantum Effects ◽

Vibrational Features

The O-H...N and O-H...O hydrogen bonds were investigated in 10-hydroxybenzo[h]quinoline (HBQ) and benzo[h]quinoline-2-methylresorcinol complex in vacuo, solvent and crystalline phases. The chosen systems contain analogous donor and acceptor moieties but differently coupled (intra- versus intermolecularly). Car–Parrinello molecular dynamics (CPMD) was employed to shed light onto principle components of interactions responsible for the self-assembly. It was applied to study the dynamics of the hydrogen bonds and vibrational features as well as to provide initial geometries for incorporation of quantum effects and electronic structure studies. The vibrational features were revealed using Fourier transformation of the autocorrelation function of atomic velocity and by inclusion of nuclear quantum effects on the O-H stretching solving vibrational Schrödinger equation a posteriori. The potential of mean force (Pmf) was computed for the whole trajectory to derive the probability density distribution and for the O-H stretching mode from the proton vibrational eigenfunctions and eigenvalues incorporating statistical sampling and nuclear quantum effects. The electronic structure changes of the benzo[h]quinoline-2-methylresorcinol dimer and trimers were studied based on Constrained Density Functional Theory (CDFT) whereas the Electron Localization Function (ELF) method was applied for all systems. It was found that the bridged proton is localized on the donor side in both investigated systems in vacuo. The crystalline phase simulations indicated bridged proton-sharing and transfer events in HBQ. These effects are even more pronounced when nuclear quantization is taken into account, and the quantized Pmf allows the proton to sample the acceptor area more efficiently. The CDFT indicated the charge depletion at the bridged proton for the analyzed dimer and trimers in solvent. The ELF analysis showed the presence of the isolated proton (a signature of the strongest hydrogen bonds) only in some parts of the HBQ crystal simulation. The collected data underline the importance of the intramolecular coupling between the donor and acceptor moieties.

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Optoelectronic Properties of Ultrathin Indium Tin Oxide Films: A First-Principle Study

Crystals ◽

10.3390/cryst11010030 ◽

2020 ◽

Vol 11 (1) ◽

pp. 30

Author(s):

Xiaoyan Liu ◽

Lei Wang ◽

Yi Tong

Keyword(s):

Film Thickness ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Density Functional ◽

Optoelectronic Properties ◽

Surface Strain ◽

Strain Effect ◽

First Principle ◽

Electrical Resistivities ◽

Ito Films

First-principle density functional theory simulations have been performed to predict the electronic structures and optoelectronic properties of ultrathin indium tin oxide (ITO) films, having different thicknesses and temperatures. Our results and analysis led us to predict that the physical properties of ultrathin films of ITO have a direct relation with film thickness rather than temperature. Moreover, we found that a thin film of ITO (1 nm thickness) has a larger absorption coefficient, lower reflectivity, and higher transmittance in the visible light region compared with that of 2 and 3 nm thick ITO films. We suggest that this might be due to the stronger surface strain effect in 1 nm thick ITO film. On the other hand, all three thin films produce similar optical spectra. Finally, excellent agreement was found between the calculated electrical resistivities of the ultrathin film of ITO and that of its experimental data. It is concluded that the electrical resistivities reduce along with the increase in film thickness of ITO because of the short strain length and limited bandgap distributions.

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Graphene adlayer growth between nonepitaxial graphene and Ni(111) substrate: a promising theoretical scheme

Physical Chemistry Chemical Physics ◽

10.1039/d0cp04667a ◽

2020 ◽

Author(s):

Lijuan Meng ◽

Jinlian Lu ◽

Yujie Bai ◽

Lili Liu ◽

Tang Jingyi ◽

...

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Chemical Vapor Deposition ◽

Molecular Dynamics Simulations ◽

Vapor Deposition ◽

Density Functional ◽

Chemical Vapor ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Dynamics Simulations

Understanding the fundamentals of chemical vapor deposition bilayer graphene growth is crucial for its synthesis. By employing density functional theory calculations and classical molecular dynamics simulations, we have investigated the...

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