First Principles Calculation of the Entropy of Liquid Aluminum

The information required to specify a liquid structure equals, in suitable units, its thermodynamic entropy. Hence, an expansion of the entropy in terms of multi-particle correlation functions can be interpreted as a hierarchy of information measures. Utilizing first principles molecular dynamics simulations, we simulate the structure of liquid aluminum to obtain its density, pair and triplet correlation functions, allowing us to approximate the experimentally measured entropy and relate the excess entropy to the information content of the correlation functions. We discuss the accuracy and convergence of the method.

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Triplet correlation functions in the Lennard‐Jones fluid: Tests against molecular dynamics simulations

The Journal of Chemical Physics ◽

10.1063/1.444514 ◽

1983 ◽

Vol 78 (1) ◽

pp. 388-398 ◽

Cited By ~ 54

Author(s):

William J. McNeil ◽

William G. Madden ◽

A. D. J. Haymet ◽

Stuart A. Rice

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Correlation Functions ◽

Lennard Jones ◽

Dynamics Simulations ◽

Triplet Correlation

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Single-Ion Thermodynamics from First Principles: Calculation of the Absolute Hydration Free Energy and Single-Electrode Potential of Aqueous Li+Usingab InitioQuantum Mechanical/Molecular Mechanical Molecular Dynamics Simulations

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.8b00729 ◽

2018 ◽

Vol 14 (12) ◽

pp. 6443-6459 ◽

Cited By ~ 6

Author(s):

Niko Prasetyo ◽

Philippe H. Hünenberger ◽

Thomas S. Hofer

Keyword(s):

Molecular Dynamics ◽

Free Energy ◽

Molecular Dynamics Simulations ◽

First Principles ◽

Electrode Potential ◽

First Principles Calculation ◽

Hydration Free Energy ◽

The Absolute ◽

Dynamics Simulations

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4H-SiC Surface Structures and Oxidation Mechanism Revealed by Using First-Principles and Classical Molecular Dynamics Simulations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.858.429 ◽

2016 ◽

Vol 858 ◽

pp. 429-432 ◽

Cited By ~ 2

Author(s):

Takahiro Yamasaki ◽

Nobuo Tajima ◽

Tomoaki Kaneko ◽

Nobutaka Nishikawa ◽

Jun Nara ◽

...

Keyword(s):

Molecular Dynamics ◽

First Principles ◽

Oxidation Mechanism ◽

Surface Structures ◽

Dynamics Simulation ◽

First Principles Calculation ◽

Oxidation Processes ◽

Classical Molecular Dynamics ◽

Structure Changes ◽

Dynamics Simulations

The 4H-SiC(000-1)C and (0001)Si surface reconstructed structures and the oxidation processes of these surfaces are investigated using a first-principles calculation method. The most stable reconstructed 4H-SiC(000-1)C and (0001)Si surfaces have p-bonded chains. In the topmost SiC bilayer, half of Si and C atoms exchange their positions and C-C or Si-Si bonds formed densely below the surfaces. When we place a SiO2 layer on the p-bonded chain (000-1)C surface, C-C bonds are formed more densely below the interface. We simulate a sequence of O2 molecules arrivals at an interface of tridymite-phase-SiO2 and 4H-SiC(000-1)C. Dissociated O atoms at the interface tended to make bonds with Si atoms. The C-C bonds in the SiC substrate break easily and a local C surface occasionally appears. We have examined how the surface structure changes through an O2 molecule exposure by using a classical molecular dynamics simulation program and confirmed the formation of C-C bonds below the surface and the interface.

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On the Entropy of the Hard Sphere Fluid

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-1-205 ◽

1991 ◽

Vol 46 (1-2) ◽

pp. 27-31 ◽

Cited By ~ 26

Author(s):

Andräs Baranyai ◽

Denis J. Evans

Keyword(s):

Computer Simulation ◽

Correlation Functions ◽

Hard Sphere ◽

Structural Information ◽

Excess Entropy ◽

Higher Order ◽

Particle Correlation ◽

Hard Sphere Fluid ◽

Three Body ◽

Fluid Configuration

AbstractThe expansion of the entropy into one-body, two-body, three-body, etc. contributions was applied to estimate the excess entropy of the hard sphere fluid. Configuration samples provided by computer simulation were used to determine the two-particle and three-particle correlation functions. The results show that even at intermediate densities a non-negligible part of the structural information is represented by four-body and higher order correlations.

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FIRST PRINCIPLES CALCULATION OF THE PHONON SPECTRA OF SOLIDS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19816181 ◽

1981 ◽

Vol 42 (C6) ◽

pp. C6-625-C6-627 ◽

Cited By ~ 2

Author(s):

P. E. Van Camp ◽

V. E. Van Doren ◽

J. T. Devreese

Keyword(s):

First Principles ◽

First Principles Calculation ◽

Phonon Spectra

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A Study on Electrochemical Machining Method in Ultrapure Water-First-Principles Molecular-Dynamics Simulations of Etching Process on Al(001) Cathode Surface-

Journal of the Japan Society for Precision Engineering ◽

10.2493/jjspe.69.1332 ◽

2003 ◽

Vol 69 (9) ◽

pp. 1332-1336

Author(s):

Hidekazu GOTO ◽

Kikuji HIROSE ◽

Yasushi TOMA ◽

Itsuki KOBATA ◽

Takashi INADA ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

First Principles ◽

Cathode Surface ◽

Electrochemical Machining ◽

Etching Process ◽

Ultrapure Water ◽

Dynamics Simulations ◽

First Principles Molecular Dynamics

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Influence of Flexible Side-Chains on the Breathing Phase Transition of Pillared Layer MOFs: A Force Field Investigation

10.26434/chemrxiv.11720679.v1 ◽

2020 ◽

Author(s):

Julian Keupp ◽

Johannes P. Dürholt ◽

Rochus Schmid

Keyword(s):

First Principles ◽

Good Accuracy ◽

Field Investigation ◽

Square Lattice ◽

Side Chain ◽

Second Step ◽

Side Chains ◽

Dynamics Simulations ◽

Complex Phenomena ◽

Closed Pore

The prototypical pillared layer MOFs, formed by a square lattice of paddle- wheel units and connected by dinitrogen pillars, can undergo a breathing phase transition by a “wine-rack” type motion of the square lattice. We studied this not yet fully understood behavior using an accurate first principles parameterized force field (MOF-FF) for larger nanocrystallites on the example of Zn 2 (bdc) 2 (dabco) [bdc: benzenedicarboxylate, dabco: (1,4-diazabicyclo[2.2.2]octane)] and found clear indi- cations for an interface between a closed and an open pore phase traveling through the system during the phase transformation [Adv. Theory Simul. 2019, 2, 11]. In conventional simulations in small supercells this mechanism is prevented by periodic boundary conditions (PBC), enforcing a synchronous transformation of the entire crystal. Here, we extend this investigation to pillared layer MOFs with flexible side-chains, attached to the linker. Such functionalized (fu-)MOFs are experimen- tally known to have different properties with the side-chains acting as fixed guest molecules. First, in order to extend the parameterization for such flexible groups, 1a new parametrization strategy for MOF-FF had to be developed, using a multi- structure force based fit method. The resulting parametrization for a library of fu-MOFs is then validated with respect to a set of reference systems and shows very good accuracy. In the second step, a series of fu-MOFs with increasing side-chain length is studied with respect to the influence of the side-chains on the breathing behavior. For small supercells in PBC a systematic trend of the closed pore volume with the chain length is observed. However, for a nanocrystallite model a distinct interface between a closed and an open pore phase is visible only for the short chain length, whereas for longer chains the interface broadens and a nearly concerted trans- formation is observed. Only by molecular dynamics simulations using accurate force fields such complex phenomena can be studied on a molecular level.

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Real-Space X-Ray Pair Distribution Function Analysis and Molecular-Dynamics Modelling of Diflunisal Channel Hydrates

10.26434/chemrxiv.12837524 ◽

2020 ◽

Author(s):

Anuradha Pallipurath ◽

Francesco Civati ◽

Jonathan Skelton ◽

Dean Keeble ◽

Clare Crowley ◽

...

Keyword(s):

Molecular Dynamics ◽

Distribution Function ◽

Structural Dynamics ◽

First Principles ◽

Pair Distribution Function ◽

Function Analysis ◽

Real Space ◽

X Ray ◽

Dynamics Modelling ◽

Dynamics Simulations

X-ray pair distribution function analysis is used with first-principles molecular dynamics simulations to study the co-operative H2O binding, structural dynamics and host-guest interactions in the channel hydrate of diflunisal.

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