Abstracts 2009

Abstract of Publication No. 592

P. S. Häfliger, S. T. Ochsenbein, B. Trusch, H.-U. Güdel and A. Furrer
Spin dynamics in the manganese tetramer compound a-MnMoO4
J. Phys.: Condens. Matter 21, 026019/1-7 (2009)      Full Text (PDF)      DOI-Link     

Abstract: a-MnMoO4 is a tetrameric magnetic cluster system which undergoes a transition to three-dimensional antiferromagnetic order at TN = 10.7 K. In the ordered state the Mn2+ spins (sn = 5/2) are ferromagnetically aligned within the tetramer, resulting in a total cluster spin S = 10. The magnetic excitation spectrum consists of eight excitation modes of tetramer origin propagating in the whole reciprocal space. From single-crystal inelastic neutron scattering investigations the three-dimensional coupling scheme is rationalized in the framework of a tetramer-based dispersion model. The tetramer states and the energy dispersion of all the magnetic excitations are described by Heisenberg-like intra- and intercluster exchange interactions, respectively, thus a-MnMoO4 is a suitable tetrameric model system to study the interplay of these interactions.

Last modified: 13.12.11 by Gabriela Frei