Structures, stabilities and electronic properties of InAs double-walled tubelike clusters and nanotubes

Abstract

The structure evolutions and electronic properties of InAs Double-Walled tubelike clusters and nanotubes are studied by first-principles theory. Tubelike clusters, In(3pk+4p)/2As(3pk+4p)/2 (p=6, 8, 10, k=3-11), and the counterpart nanotubes, (m,n)@(2m,2n) (m=n=3,4,5), are analyzed. All geometric structures of clusters and nanotubes are optimized by using density functional theory with generalized gradient approximation, and they obey the Euler formula. The tube diameter formula is obtained. Size-dependent properties of clusters and nanotubes, such as binding energy, HOMO-LUMO gaps, density of state and energy band structures are calculated and discussed. The results show that both [6,k]@[12,k+2] and (3,3)@(6,6) possess relatively high stabilities in the corresponding systems. They also explain why the long and stable tublike clusters can be successfully obtined, and why InAs nanotubes can be synthesized experimentally. All of the double-walled tubelike clusters and nanotubes possess the characteristics of semiconductor.