Anomalous temperature dependences of the susceptibility for the one-3d- electron cation

TL;DR

This study investigates the unusual temperature dependence of magnetic susceptibility in 3d-electron cations, revealing that spin-orbit coupling and lattice distortions significantly influence magnetic properties.

Contribution

It demonstrates that even weak spin-orbit coupling affects 3d-electron ions, challenging the assumption of free S=1/2 spin behavior in solids containing Ti 3+ and V 4+ ions.

Findings

Anomalous chi(T) temperature dependence observed.

Spin-orbit coupling influences magnetic susceptibility.

Lattice distortions affect magnetic properties.

Abstract

We have studied properties of the one-3d-electron cation (Ti 3+, V 4+ ions) under the action of the low-symmetry crystal field in the presence of the spin- orbit coupling. Very anomalous temperature dependences of the magnetic susceptibility chi (T) have been obtained as resulting from the off-cubic lattice distortion provided the intra-atomic spin-orbit coupling is taken into account. It indicates that, despite of the weakness of the spin-orbit coupling, the one 3d electron in a solid cannot be treated as a free S=1/2 spin. The same holds for compounds containing the Ti 3+ and V4+ ions.