Free-energy Calculations Using Classical Molecular Simulation: Application to the Determination of the Melting Point and Chemical Potential of a Flexible RDX Model.

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F16%3A00461336" target="_blank" >RIV/67985858:_____/16:00461336 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/44555601:13440/16:43887611

Výsledek na webu

<a href="http://dx.doi.org/10.1039/c5cp06164d" target="_blank" >http://dx.doi.org/10.1039/c5cp06164d</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c5cp06164d" target="_blank" >10.1039/c5cp06164d</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Free-energy Calculations Using Classical Molecular Simulation: Application to the Determination of the Melting Point and Chemical Potential of a Flexible RDX Model.

Popis výsledku v původním jazyce

We present an extension of various free-energy methodologies to determine the chemical potential of the solid and liquid phases of a fully-flexible molecule using classical simulation. The methods are applied to the Smith-Bharadwaj atomistic potential representation of cyclotrimethylene trinitramine (RDX), a well-studied energetic material, to accurately determine the solid and liquid phase Gibbs free energies, and the melting point (T-m). We outline an efficient technique to find the absolute chemical potential and melting point of a fully-flexible molecule using one set of simulations to compute the solid absolute chemical potential and one set of simulations to compute the solid-liquid free energy difference. With this combination, only a handful of simulations are needed, whereby the absolute quantities of the chemical potentials are obtained, for use in other property calculations, such as the characterization of crystal polymorphs or the determination of the entropy. Using the LAMMPS molecular simulator, the Frenkel and Ladd and pseudo-supercritical path techniques are adapted to generate 3rd order fits of the solid and liquid chemical potentials. Results yield the thermodynamic melting point T-m = 488.75 K at 1.0 atm. We also validate these calculations and compare this melting point to one obtained from a typical superheated simulation technique.

Název v anglickém jazyce

Free-energy Calculations Using Classical Molecular Simulation: Application to the Determination of the Melting Point and Chemical Potential of a Flexible RDX Model.

Popis výsledku anglicky

We present an extension of various free-energy methodologies to determine the chemical potential of the solid and liquid phases of a fully-flexible molecule using classical simulation. The methods are applied to the Smith-Bharadwaj atomistic potential representation of cyclotrimethylene trinitramine (RDX), a well-studied energetic material, to accurately determine the solid and liquid phase Gibbs free energies, and the melting point (T-m). We outline an efficient technique to find the absolute chemical potential and melting point of a fully-flexible molecule using one set of simulations to compute the solid absolute chemical potential and one set of simulations to compute the solid-liquid free energy difference. With this combination, only a handful of simulations are needed, whereby the absolute quantities of the chemical potentials are obtained, for use in other property calculations, such as the characterization of crystal polymorphs or the determination of the entropy. Using the LAMMPS molecular simulator, the Frenkel and Ladd and pseudo-supercritical path techniques are adapted to generate 3rd order fits of the solid and liquid chemical potentials. Results yield the thermodynamic melting point T-m = 488.75 K at 1.0 atm. We also validate these calculations and compare this melting point to one obtained from a typical superheated simulation technique.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

—

Projekt

<a href="/cs/project/GA13-02938S" target="_blank" >GA13-02938S: Řízená asociace polyelektrolytových kopolymerů se surfaktanty ve vodných roztocích</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Chemistry Chemical Physics

ISSN

1463-9076

e-ISSN

—

Svazek periodika

18

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

11

Strana od-do

7841-7850

Kód UT WoS článku

000372229700028

EID výsledku v databázi Scopus

2-s2.0-84960935550