Vibrational energies and thermal expansion of layered compounds: MgCl2

Autor:	Neil L. Allan, M.R. Soriano, GD Barrera
Rok vydání:	2001
Předmět:	Computational chemistry Chemistry Phase stability Ab initio quantum chemistry methods Molecular vibration Perpendicular General Physics and Astronomy Free energies Density functional theory Physical and Theoretical Chemistry Anisotropy Molecular physics Thermal expansion
Zdroj:	Chemical Physics Letters. 350:543-550
ISSN:	0009-2614
DOI:	10.1016/s0009-2614(01)01332-x
Popis:	Full dynamic free energy minimisation is used to study the stability of different polymorphs of MgCl 2 , with a new set of interionic potentials derived from ab initio calculations using density functional theory. The calculated difference in free energies between the α- and β-phases is extremely small: the vibrational contribution reverses the relative ordering of these two structures obtained in the static limit. We predict the thermal expansion of both forms is highly anisotropic and that, unusually, above ≈60 K the expansion is larger parallel than perpendicular to the layers.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::87fd54d05c978c27116849d7c962de7f https://doi.org/10.1016/s0009-2614(01)01332-x Zobrazit plný text záznamu Full Text from ScienceDirect