ENERGY-BANDS, SPIN-DENSITY AND DIMERIZATION IN ORGANIC FERROMAGNETS

We carry out numerical studies based on our theoretical model with int erchain interaction in a quasi-one-dimensional organic ferromagnet, Co nsidering the topology of the system, we propose an interchain couplin g which alternates in size and in sign along each chain, We study the splitting of energy levels with respect to different chains and examin e ferromagnetic order and dimerization as a function of the coupling s trength. II is shown that at a critical value of the coupling, the ene rgy gap and dimerization disappear. In this case, spin density wave (S DW) is changed dramatically and spin density at each site along each c hain has the same sign and alternating size. The oscillatory part of i nterchain coupling reduces the dimerization and the amplitude of SDW. The interchain coupling destabilizes the ferromagnetic state of the sy stem. (C) 1998 Elsevier Science B.V. All rights reserved.