Periodic GFN2‑xTB in CP2K: Multipolar Ewald Electrostatics, k‑Point Sampling, and Transferability Benchmarks for Solids
Extended tight-binding methods are attractive for condensed-phase simulations because they retain an explicit electronic Hamiltonian at a cost far below conventional density functional theory. Their transferability to periodic materials, however, cannot be assessed reliably without a genuinely periodic Hamiltonian, Bri...