Detail publikace

Combined quantum-mechanical and Calphad approach to description of heat capacity of pure elements below room temperature

PAVLŮ, J. ŘEHÁK, P. VŘEŠŤÁL, J. ŠOB, M.

Anglický název

Combined quantum-mechanical and Calphad approach to description of heat capacity of pure elements below room temperature

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

en

Originální abstrakt

Einstein temperature(TE) wasdeterminedby fitting ofexperimentalheatcapacitydatabytheEinstein function onlywhichensuresthatitwillrepresenttheharmonicvibrationalGibbsenergyonly.Thevalues of theelectronicandanharmoniccontributionstoGibbsenergy(heatcapacity)of51elementsinstable state aredeterminedby fitting theparametersofpolynomialsdescribingthesecontributionstoSGTE data at Tlim. PolynomialspublishedbyChenandSundman(2001)wereused.Parameters a, b, and c of those polynomialshaveaparticularphysicalmeaninginthetemperatureinterval(0oToTlim) (inK) only (Tlim is thelow-temperaturelimitofvalidityofSGTEdata).Forillustration,theresultsofcalculation of heatcapacitiesinlow-temperatureregionperformedbyPHONsoftwarearepresented.Gainedther- modynamic datamakeitpossibletoperformcorrectCalphadmodelingofphasediagramsbelowroom temperature;forthispurpose,theSGTE-typeformulas(intheformofG-HSER)forGibbsenergiesof51 elements studiedareprovided.Theaimofthispaperistoshowrelativesimpleandphysicallycorrect waytoextendtheSGTEdatato0K,whichcanbesupportedbyabinitiophononcalculationsinthe future.

Anglický abstrakt

Einstein temperature(TE) wasdeterminedby fitting ofexperimentalheatcapacitydatabytheEinstein function onlywhichensuresthatitwillrepresenttheharmonicvibrationalGibbsenergyonly.Thevalues of theelectronicandanharmoniccontributionstoGibbsenergy(heatcapacity)of51elementsinstable state aredeterminedby fitting theparametersofpolynomialsdescribingthesecontributionstoSGTE data at Tlim. PolynomialspublishedbyChenandSundman(2001)wereused.Parameters a, b, and c of those polynomialshaveaparticularphysicalmeaninginthetemperatureinterval(0oToTlim) (inK) only (Tlim is thelow-temperaturelimitofvalidityofSGTEdata).Forillustration,theresultsofcalculation of heatcapacitiesinlow-temperatureregionperformedbyPHONsoftwarearepresented.Gainedther- modynamic datamakeitpossibletoperformcorrectCalphadmodelingofphasediagramsbelowroom temperature;forthispurpose,theSGTE-typeformulas(intheformofG-HSER)forGibbsenergiesof51 elements studiedareprovided.Theaimofthispaperistoshowrelativesimpleandphysicallycorrect waytoextendtheSGTEdatato0K,whichcanbesupportedbyabinitiophononcalculationsinthe future.

Klíčová slova anglicky

Einstein temperature; Heat capacity; SGTE data; Pure elements; Zero Kelvin; Low temperature

Rok RIV

2015

Vydáno

01.12.2015

Nakladatel

PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND

ISSN

0364-5916

Ročník

51

Číslo

1

Strany od–do

161–171

Počet stran

11

BIBTEX


@article{BUT118708,
  author="Jana {Pavlů} and Petr {Řehák} and Jan {Vřešťál} and Mojmír {Šob},
  title="Combined quantum-mechanical and Calphad approach to description of heat capacity of pure elements below room temperature",
  year="2015",
  volume="51",
  number="1",
  month="December",
  pages="161--171",
  publisher="PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND",
  issn="0364-5916"
}