Chemical Bonding in Compounds of the CuAl2 Family: MnSn2, FeSn2 and CoSn2

Authors:
Publisher website
Google Scholar
Abstract
A model for the chemical bonding in the isostructural intermetallic compounds MnSn2, FeSn2 and CoSn2, crystallising in the CuAl2‐type structure, is developed. The description is based on quantum‐chemical calculations applying the electron localisability approach as well as on experimental results obtained from Raman spectroscopy, Hall effect and electrical resistivity measurements on oriented single crystals. The analysis of the chemical bonding reveals four different covalent interactions leading to the formation of interpenetrating 63 nets of tin and chains of transition‐metal atoms T (T=Mn, Fe or Co) along [001], which are interconnected by three‐centre bonds. Polarised Raman measurements on oriented single crystals allowed the determination of the bond strengths, resulting in a bond order of 0.5 within the 63 nets, while the three‐centre interactions show bond orders of up to 1. Measurements show a metal‐like temperature dependence of the resistivity. A comparison of the results with the bonding models obtained for the isostructural compounds CuAl2, TiSb2 and VSb2 reveals the influence of the main‐group element on the connectivity pattern.

This publication has 60 references indexed in Scilit: