Metamagnetism in one dimensional systems with edge sharing CuO polyhedra

We study a Heisenberg chain with nearest-neighbor (NN) J(1) and next-NN J(2 ) exchange interactions with anisotropies Delta (1) and Delta (2), respecti vely. We investigate by analytical and numerical methods the region of para meters for which there is a jump in the magnetization, M, as a function of magnetic field B. Some materials with edge sharing CuO polyhedra are candid ates to show an abrupt change in M(B). (C) 2001 Published by Elsevier Scien ce B.V.