Quantum dynamics in high‐spin molecules, spin dendrimers, and spin lattices

Abstract

AbstractWe perform spin dynamics in strongly correlated electron–spin systems to clarify the relationship between the phase relaxation and the structure of the spin systems. The interaction among spins is considered to be Heisenberg‐type exchange. The quantum Liouville approach is used for the dynamics involving the relaxation processes of the systems, which is considered to originate in spin–phonon and electron spin–nuclear spin interactions. As a first step of our study, to examine the effects of the structures on the phase relaxation, we consider the phenomenological relaxation parameters for the relaxation terms of quantum Liouville equation, and perform the spin dynamics in four types of four electron–spin systems that have linear, square, star (dendritic structure), and tetrahedral structures. The results of our calculation indicated the possibility for the control of the phase relaxation by the change of the structure in spin clusters. Possible implications of our results are related to the single‐molecule magnets, ESR‐STM detection of spins, and related spin‐transition phenomena (decoherence and population relaxation). © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005