Glass Transition and Structure of Organic Polymers from All-Atom Molecular Simulations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F23%3A43927917" target="_blank" >RIV/60461373:22340/23:43927917 - isvavai.cz</a>

Výsledek na webu

<a href="https://pubs.acs.org/doi/10.1021/acs.iecr.3c03038" target="_blank" >https://pubs.acs.org/doi/10.1021/acs.iecr.3c03038</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.iecr.3c03038" target="_blank" >10.1021/acs.iecr.3c03038</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Glass Transition and Structure of Organic Polymers from All-Atom Molecular Simulations

Popis výsledku v původním jazyce

Molecular dynamics simulations of polymer samples with all-atom resolution provide important insight into the relationship between the atom-level structure and macroscopic properties of polymers. The computational setup of molecular simulations in such a case deserves to be validated, paying attention not to overlook various aspects or inferior settings or postprocessing analyses that have the potential to distort the simulation outcome or at least to make the simulated ensemble too incompatible with its experimental counterparts, such as their polydispersity, initial conformation, or thermal history of the samples. The accuracy of the simulation results obtained from existing all-atom nonpolarizable force fields for three selected polymers is independently benchmarked with respect to the polymer densities and glass transition temperatures. Errors of structural or thermodynamic properties arising due to insufficient sample equilibration or inadequate simulation setup are quantified. Special attention is paid to the selection of reference literature data for polymer systems that are well characterized and as similar as possible to the computationally treated samples. Very different performances of predictions of the glass transition temperatures occur among the individual target polymers, with both their sampling uncertainty and errors from reference experimental data ranging from acceptable below 10 K to highly unsatisfactory 100 K in individual cases. The accuracy of the predicted glass transition temperature is found to be higher for polymers exhibiting faster internal dynamics and distinct trend shifts between the glass and the liquid. On the contrary, when the glass transition occurs gradually over a wider temperature range, it becomes very difficult to capture the adequate transition temperature within molecular simulations, regardless of the evaluation protocol used. Bulk density proves to be the most reliable observable for subsequent trend shift analyses, which typically yield similar results regardless of performing equilibrium or nonequilibrium simulations and adopting the bilinear or hyperbolic regression analyses. © 2023 The Authors. Published by American Chemical Society.

Název v anglickém jazyce

Glass Transition and Structure of Organic Polymers from All-Atom Molecular Simulations

Popis výsledku anglicky

Molecular dynamics simulations of polymer samples with all-atom resolution provide important insight into the relationship between the atom-level structure and macroscopic properties of polymers. The computational setup of molecular simulations in such a case deserves to be validated, paying attention not to overlook various aspects or inferior settings or postprocessing analyses that have the potential to distort the simulation outcome or at least to make the simulated ensemble too incompatible with its experimental counterparts, such as their polydispersity, initial conformation, or thermal history of the samples. The accuracy of the simulation results obtained from existing all-atom nonpolarizable force fields for three selected polymers is independently benchmarked with respect to the polymer densities and glass transition temperatures. Errors of structural or thermodynamic properties arising due to insufficient sample equilibration or inadequate simulation setup are quantified. Special attention is paid to the selection of reference literature data for polymer systems that are well characterized and as similar as possible to the computationally treated samples. Very different performances of predictions of the glass transition temperatures occur among the individual target polymers, with both their sampling uncertainty and errors from reference experimental data ranging from acceptable below 10 K to highly unsatisfactory 100 K in individual cases. The accuracy of the predicted glass transition temperature is found to be higher for polymers exhibiting faster internal dynamics and distinct trend shifts between the glass and the liquid. On the contrary, when the glass transition occurs gradually over a wider temperature range, it becomes very difficult to capture the adequate transition temperature within molecular simulations, regardless of the evaluation protocol used. Bulk density proves to be the most reliable observable for subsequent trend shift analyses, which typically yield similar results regardless of performing equilibrium or nonequilibrium simulations and adopting the bilinear or hyperbolic regression analyses. © 2023 The Authors. Published by American Chemical Society.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/GM23-05476M" target="_blank" >GM23-05476M: Vývoj ab initio modelování pro neuspořádané molekulární polovodiče</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

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

Název periodika

INDUSTRIAL &amp; ENGINEERING CHEMISTRY RESEARCH

ISSN

0888-5885

e-ISSN

1520-5045

Svazek periodika

62

Číslo periodika v rámci svazku

49

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

21437-21448

Kód UT WoS článku

001126781200001

EID výsledku v databázi Scopus

2-s2.0-85179618031