Exact solution of the $XXZ$ Heisenberg model of spin $S$

She generalization of the $XXZ$ Heisenberg model to the case of arbitrary spin with anysotropy of the“light plane” type i s studied. She ground state of the system, it's excitation spectrum and the corresponding scattering matrices are found. She magnetic susceptibility of the model under small magnetic fields and the Low-temperature heat capacity are calculated. Bibl. – 31.