Heisenberg‐type and double exchange in mixed‐valence clusters

M. I. Belinskii, V. Ya. Gamurar, B. S. Tsukerblat

Research output: Contribution to journalArticlepeer-review

17 Scopus citations

Abstract

A theory of the vibronic reduction of the energy levels of transition metal mixed valence clusters is developed. The 2T2(t2) ‐ 3T1(t 22)‐type system is considered in detail. The vibronic model takes into account the interaction with the totally symmetric (A1) mode as well as the interaction with the Jahn‐Teller tetragonal (E) displacement of each d‐ion ligand. The dispersion of crystal vibrations is considered. The correlation interionic interactions via the phonon field are found and discussed in detail. It is indicated that the Heisenberg‐type exchange interaction is partially reduced by the Jahn‐Teller interaction, and the expressions for the reduction factors are calculated. The double exchange parameter is reduced completely by Jahn‐Teller and totally symmetric vibrations. It is shown that the reduction of the double exchange leads to the antiferromagnetic ground state in mixed valence systems with ferromagnetic sround state arising from the double exchange.

Original languageEnglish
Pages (from-to)555-569
Number of pages15
Journalphysica status solidi (b)
Volume135
Issue number2
DOIs
StatePublished - 1 Jan 1986
Externally publishedYes

Fingerprint

Dive into the research topics of 'Heisenberg‐type and double exchange in mixed‐valence clusters'. Together they form a unique fingerprint.

Cite this