Atomic Structure and Sound Wave in Liguid Alloys incorporating with Metal-Nonmetal Transition

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A large temerature dependence of the electronic properties, heats and structure factors in liquid tellurium and their alloys has been observed. These anomalies are due to the transition from non-metallic to metallic state incorporating to the recombination of bonding in the system. The large specific heats in liquid Se-Te and IIIb-Te alloys are fully explained in terms of Schottky-sype specific heat based on a gradual transition. Using this thermodynamic data, the structure factors of these systems can be analysed in the atomic scale. In particular, the temperature dependence of measured structural functions of liquid Se-Te alloys could be explained by a gradual transition from two-fold coordinate component (non-metallic) to the three-fold one (metallic)The compressibilities obtained from the sound velocity for these system show a large excess value which is expressed by a kind of lorezian curve. We also found that this excess value is phenomenologically propotional to a product of volume difference (V_M-V_N) between metallic and nonmetallic state and the differentiation of the metallic fraction with the pressure. The ration of the dulk viscosity and the shear viscosity of these system also shows a minimum at the transition temperatureIn conclusion this kind of transition is classified a higher order transition.