  We present a detailed study of a model for strain-induced metal-insulator
phase coexistence in perovskite manganites. Both nanoscale and mesoscale
inhomogeneities are self-consistently described using atomic scale modes and
their associated constraint equations. We also examine the stability of domain
configurations against uniform and nonuniform modifications of domain walls.
Our results show that the long range interactions between strain fields and the
complex energy landscape with multiple metastable states play essential roles
in stabilizing metal-insulator phase coexistence, as observed in perovskite
manganites. We elaborate on the modes, constraint equations, energies, and
energy gradients that form the basis of our simulation results.
