Beryllium, tungsten and their alloys Be2W and Be12W: Surface defect energetics from density functional theory calculations

•Surface energetics of beryllium–tungsten alloys depends strongly on the surface orientation and termination.•Energetics is strongly correlated to the type, number, and distances of nearest neighbor atoms.•Plane-wave density functional theory calculations of surface binding energies, adatom energies, and step edges.•Tungsten atoms bind stronger on beryllium surfaces than vice versa.