Abstract :
The method of independent paris and sites (IPS) is used to study the ordering behavior of the feldspar mineral albite.Unlike recent models,in which local charge neutrality was not introduced, here it is imposed by using Andersen,s two-dimensional model of albite.Even though the same approximation (IPS method) has been used in both Andersen,s model and the presen treatment, the final results for the ordering behavior are quite different, in the sense that a metastable (soild) phase is predicted at some temperatures in the former, and no such behavior is predicted in the latter. One should therefore expect that the size of the local stuctural unit used to impose electroneutrality can be very important in model calculations on albite.
