Green–Kubo expressions for transport coefficients from dissipative particle dynamics simulations revisited

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F24%3A00580367" target="_blank" >RIV/67985858:_____/24:00580367 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/44555601:13440/24:43898017

Výsledek na webu

<a href="https://hdl.handle.net/11104/0349155" target="_blank" >https://hdl.handle.net/11104/0349155</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d3cp03791f" target="_blank" >10.1039/d3cp03791f</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Green–Kubo expressions for transport coefficients from dissipative particle dynamics simulations revisited

Popis výsledku v původním jazyce

This article addresses the debate about the correct application of Green–Kubo expressions for transport coefficients from dissipative particle dynamics simulations. We demonstrate that the Green–Kubo expressions are valid provided that the dynamic model conserves the physical property, whose transport is studied, and the fluctuations satisfy detailed balance. As a result, the traditional expressions used in molecular dynamics can also be applied to dissipative particle dynamics simulations. However, taking the calculation of the shear viscosity as a paradigmatic example, a random contribution, whose strength scales as 1/dt 1/2, with dt the time-step, can cause difficulties if the stress tensor is not separated into the different contributions. We compare our expression to that of Ernst and Brito (M. H. Ernst and R. Brito, Europhys. Lett., 2006, 73, 183–189), which arises from a diametrically different perspective. We demonstrate that the two expressions are completely equivalent and find exactly the same result both analytically and numerically. We show that the differences are not due to the lack of time-reversibility but instead from a preaveraging of the random contributions. Despite the overall validity of Green–Kubo expressions, we find that the Einstein–Helfand relations (D. C. Malaspina et al. Phys. Chem. Chem. Phys., 2023, 25, 12025–12040) do not suffer from the need to decompose the stress tensor and can readily be used with a high degree of accuracy. Consequently, Einstein–Helfand relations should be seen as the preferred method to calculate transport coefficients from dissipative particle dynamics simulations.

Název v anglickém jazyce

Green–Kubo expressions for transport coefficients from dissipative particle dynamics simulations revisited

Popis výsledku anglicky

This article addresses the debate about the correct application of Green–Kubo expressions for transport coefficients from dissipative particle dynamics simulations. We demonstrate that the Green–Kubo expressions are valid provided that the dynamic model conserves the physical property, whose transport is studied, and the fluctuations satisfy detailed balance. As a result, the traditional expressions used in molecular dynamics can also be applied to dissipative particle dynamics simulations. However, taking the calculation of the shear viscosity as a paradigmatic example, a random contribution, whose strength scales as 1/dt 1/2, with dt the time-step, can cause difficulties if the stress tensor is not separated into the different contributions. We compare our expression to that of Ernst and Brito (M. H. Ernst and R. Brito, Europhys. Lett., 2006, 73, 183–189), which arises from a diametrically different perspective. We demonstrate that the two expressions are completely equivalent and find exactly the same result both analytically and numerically. We show that the differences are not due to the lack of time-reversibility but instead from a preaveraging of the random contributions. Despite the overall validity of Green–Kubo expressions, we find that the Einstein–Helfand relations (D. C. Malaspina et al. Phys. Chem. Chem. Phys., 2023, 25, 12025–12040) do not suffer from the need to decompose the stress tensor and can readily be used with a high degree of accuracy. Consequently, Einstein–Helfand relations should be seen as the preferred method to calculate transport coefficients from dissipative particle dynamics simulations.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

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

1463-9084

Svazek periodika

26

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

1328-1339

Kód UT WoS článku

001129299200001

EID výsledku v databázi Scopus

2-s2.0-85180093779