Twister: Construction and structural relaxation of commensurate moire superlattices

Introduction of a twist between layers of two-dimensional materials which leads to the formation of a moire pattern is an emerging pathway to tune the electronic, vibrational and optical properties. The fascinating properties of these systems is often linked to large-scale structural reconstruction of the moire pattern. Hence, an essential first step in the theoretical study of these systems is the construction and structural relaxation of the atoms in the moire superlattice. We present the Twister package, a collection of tools that constructs commensurate superlattices for any combination of 2D materials and also helps perform structural relaxations of the moire superlattice. Twister constructs commensurate moire superlattices using the coincidence lattice method and provides an interface to perform structural relaxations using classical forcefields.