In this paper we demonstrate, using density-functional tight-binding theory
, that certain classes of germanium-based tubular nanostructures are stable
and energetically viable. Specifically, we consider GeH nanotubes. The str
uctures adopted by these nanotubes are very similar to those of previously
reported silane and siloxene nanotubes. The Ge-based nanotubes have a semic
onducting gap which is dependent on the tube diameter. (C) 2001 Elsevier Sc
ience Ltd. All rights reserved.