First-Principles Study of Structural and Electronic Properties of Germanene

Harihar Behera, Gautam Mukhopadhyay

Published 2011-11-28Version 1

The ground state structural and electronic properties of germanene (the germanium analogue of graphene) are investigated using first-principles calculations. On structure optimization, the graphene-like honeycomb structure of germanene turns out as buckled (buckling parameter $\Delta = 0.635$ \AA) in contrast with graphene's planar structure (buckling parameter $\Delta = 0.0$ \AA). In spite of this, germanene has similar electronic structure as that of graphene. While corroborating the reported results, we newly predict the in-plane contraction of hexagonal Ge with (thermal) stretching along the "c" axis, akin to a phenomenon observed in graphite.