Glass transition of hard sphere systems-Molecular dynamics and density functional approaches

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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Density functional study of non-isothermal hard sphere fluids

Molecular Physics ◽

10.1080/00268976.2021.1875077 ◽

2021 ◽

pp. e1875077

Author(s):

Wenhan Jia ◽

Isamu Kusaka

Keyword(s):

Hard Sphere ◽

Density Functional ◽

Functional Study ◽

Density Functional Study

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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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