Amorphous InSb: Longer bonds yet higher density

Results of x-ray absorption studies of the structure of amorphous InSb are reported. We demonstrate that approximately 1% bond elongation in the amorphous phase (as compared to the crystalline phase) is accompanied by a counterintuitive increase (approximately 5%) in density. We argue that this controversy is due to the formation of wrong bonds in the amorphous phase with both Sb and In atoms effectively preserving their tetrahedral coordination. Our results additionally offer an alternative interpretation of the semiconductor-metal transition observed upon melting of InSb. (C) 2010 American Institute of Physics. [doi:10.1063/1.3436592]