Crossover of the magnetic sublevels in spin frustrated clusters: The role of static and dynamic deformations

Tarantul A, Tsukerblat B, Müller A. Crossover of the magnetic sublevels in spin frustrated clusters: The role of static and dynamic deformations. SOLID STATE SCIENCES. 2008;10(12):1814-1819.We model the magnetic behavior of spin frustrated trinuclear clusters in the region of field induced crossover of the levels. The emphasis is made on a competitive role of the antisymmetric (AS) exchange and static structural distortions as well as on the consequences of the dynamic pseudo-Jahn-Teller (JT) instability. We employ the three-spin model for the cluster anion present in K-6[(V15As6O42)-As-IV(H2O)]center dot 8H(2)O (V-15 cluster) and analyze the role of different components of AS in the half step magnetization. Both types of deformations (static and dynamic) are shown to be competitive with the AS exchange and tend to reduce the magnetic anisotropy caused by AS. (C) 2008 Elsevier Masson SAS. All rights reserved