Chemical bonding, elasticity, and valence force field models: A case study for α-Pt2Si and PtSi

J. E. Klepeis, O. Beckstein, O. Pankratov, G. L.W. Hart

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

We have carried out a detailed study of the chemical bonding for two room-temperature stable platinum silicide phases, tetragonal α-Pt2Si and orthorhombic PtSi. An analysis of the valence electronic charge density reveals surprising evidence of covalent three-center bonds in both silicide phases, as well as two-dimensional metallic sheets in α-Pt2Si. These elements of the bonding are further analyzed by constructing valence force field models using the results from recent first principles calculations of the six (nine) independent, nonzero elastic constants of α-Pt2Si (PtSi). The resulting volume-, radial-, and angular-dependent force constants provide insight into the relative strength of various bonding elements as well as the trends observed in the elastic constants themselves. The valence force field analysis yields quantitative information about the nature of the chemical bonding that is not easily discernible from the more qualitative charge density plots. More generally, this study demonstrates that the detailed variations in the elastic constants of a material contain useful information about the chemical bonds that can be extracted using valence force field models. Inversely, these models also allow for identification of specific elements of the chemical bonding with particular trends in the elastic constants, both within a given material and among a class of related materials.

Original languageEnglish (US)
Article number155110
Pages (from-to)1551101-15511015
Number of pages13959915
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume64
Issue number15
StatePublished - Oct 15 2001
Externally publishedYes

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint

Dive into the research topics of 'Chemical bonding, elasticity, and valence force field models: A case study for α-Pt<sub>2</sub>Si and PtSi'. Together they form a unique fingerprint.

Cite this