On a Quantum Plateau of Magnetization in Metal–Organic Quasi-One-Dimensional Ferrimagnets.

The possibility of realizing a quantum plateau of magnetization in [Mn(hfac)[sub 2]BNO[sub R]] metal–organic compounds is investigated theoretically. A model of a one-dimensional ferrimagnetic chain (5/2, 1) is used for calculating the magnetization as a function of an external field by the method of discrete path integral representation (DPIR). Within this model, the coexistence of classical and quantum plateaus of magnetization is revealed. It is shown that the critical field H[sub c][sub 1] that destroys the classical plateau (ground-state magnetization) is determined by the optical gap in zero field, which is estimated by the matrix-product method and a numerical method of exact diagonalization (recursion method). © 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]