LOW-DIMENSIONAL ORDERING ON A LATTICE MODEL

A simple d-dimensional lattice model is proposed, incorporating some d egree of frustration and thus capable of describing some aspects of mo lecular orientation in covalently bound molecular solids. For d = 2 th e model is shown to be equivalent to the standard two-dimensional Isin g model, while for d > 2 it describes a peculiar transition from an is otropic high temperature phase to a low-dimensional anisotropic low te mperature state. A general mean field analysis is presented and compar ed to some exact limit properties.