Magnetic properties of a transverse spin-1 Ising model with random longitudinal field

Using an expansion technique for cluster identities of spin-1 localised spin systems, we have investigated the phase diagram of a transverse spin-1 Ising ferromagnet with random longitudinal magnetic field. The longitudinal and transverse magnetizations, the quadrupolar moments and the phase diagrams are calculated using a bimodal distribution of the longitudinal magnetic field. General formula, applicable to structures with arbitrary coordination number N, are given.