Germanium semiconductors liquid transitions

Also, of course, there was always the icy grip of cumbersome liquid or compressed gaseous helium that the materials had to be held in if they were to superconduct. Try as they might, researchers could not get the transition temperature of all their materials up to easily manageable levels. By 1973, although several hundred materials were known to superconduct, the best that scientists were able to achieve was a Tc of 23.2° K (-418° F] with a compound of three parts niobium and one of germanium, the latter a hard metalloid with, ironically, semiconductor properties. 

Kresse, G. and Hafner, J., Ab initio molecular-dynamics simulation of the liquid-metal-amorphous-semiconductor transition in germanium, Phys. Rev. B, 49, 14251, 1994. 

Simulation of the Liquid-Metal Amorphous Semiconductor Transition in Germanium. 

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