Evaluation of accuracy of ideal-gas heat capacity and entropy calculations by density functional theory (DFT) for rigid molecules

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F12%3A00437181" target="_blank" >RIV/68378271:_____/12:00437181 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1021/je201095b" target="_blank" >http://dx.doi.org/10.1021/je201095b</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/je201095b" target="_blank" >10.1021/je201095b</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Evaluation of accuracy of ideal-gas heat capacity and entropy calculations by density functional theory (DFT) for rigid molecules

Popis výsledku v původním jazyce

Quantum mechanical calculations, coupled with statistical thermodynamics, provide a means to obtain thermodynamic properties of ideal gas. In this work, we performed density functional theory (DFT) and statistical thermodynamic calculations of ideal-gasheat capacities and entropies for a set of 93 rigid molecules, which do not contain large amplitude motions, such as internal rotations or ring puckering, and for which reliable reference data were found in the literature. The effect of the size of basissets and scale factors was systematically examined and statistically evaluated. The absolute average percentage deviations of the heat capacities and entropies calculated using unscaled harmonic frequencies from reference values were less than 2.5% forall of the basis sets studied. Both heat capacities and entropies were, however, systematically underestimated, and the relative deviations of heat capacities showed a significant temperature dependence with a maximum deviation near ambie

Název v anglickém jazyce

Evaluation of accuracy of ideal-gas heat capacity and entropy calculations by density functional theory (DFT) for rigid molecules

Popis výsledku anglicky

Quantum mechanical calculations, coupled with statistical thermodynamics, provide a means to obtain thermodynamic properties of ideal gas. In this work, we performed density functional theory (DFT) and statistical thermodynamic calculations of ideal-gasheat capacities and entropies for a set of 93 rigid molecules, which do not contain large amplitude motions, such as internal rotations or ring puckering, and for which reliable reference data were found in the literature. The effect of the size of basissets and scale factors was systematically examined and statistically evaluated. The absolute average percentage deviations of the heat capacities and entropies calculated using unscaled harmonic frequencies from reference values were less than 2.5% forall of the basis sets studied. Both heat capacities and entropies were, however, systematically underestimated, and the relative deviations of heat capacities showed a significant temperature dependence with a maximum deviation near ambie

Druh

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

CEP obor

BM - Fyzika pevných látek a magnetismus

OECD FORD obor

—

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2012

Kód důvěrnosti údajů

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

Název periodika

Journal of Chemical and Engineering Data

ISSN

0021-9568

e-ISSN

—

Svazek periodika

57

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

6

Strana od-do

227-232

Kód UT WoS článku

000298978900035

EID výsledku v databázi Scopus

—