@pranavkumar: I'll try to summarize some disorder methods below from your question on disordering:

The goal of SQS is to create a small supercell that approximates random mixing ("small" here being something like 16 atoms for a binary fcc alloy). The method populates atomic positions in the supercell with species such that the correlation function up to a certain number of nearest neighbors within some radius match the correlation function of a truly random alloy. The approach ATAT uses performs Monte Carlo to search the space of configurations of species in a random alloy. SQS are based o…