PAOFLOW: A utility to construct and operate on ab initio Hamiltonians from the Projections of electronic wavefunctions on Atomic Orbital bases (PAO), including characterization of topological materials

Rapid progression of computational technology during the past half century allows material sceintists to predict electronic and bulk properties of increasingly complex systems. PAOFLOW is a utility for the analysis and characterization of these properties from the output of any electronic structure calculation in Density Functional Theory (DFT). By exploiting an efficient procedure to project the full plane-wave solution of the original DFT Hamiltonian to a reduced space of atomic orbitals (Projection on Atomic Orbitals, or PAO) we can calculate a plethora of quantities with a negligible computational cost. This code, written entirely in Python under GPL 3.0 or later, opens the way to the high-throughput computational characterization of materials at an unprecedented scale.