Recent development in the study of the properties of liquid metals is reviewed. Forcusing the main interest to the remarkable experiment, it is considered how to understand the physical features of liquid metals. The outline of the microscopic structure of ions and the electronic structure of liquid metals are described. On the ionic structure two-body correlation concentrating on the hard sphere model, the pair theory and its limit, time-space correlation, and some topics of three-body correlation and critical opalescence are mentioned. The electronic structure is discussed from two situation, namely nearly free electron model and the model by Mott.
The crystal structures of the quaternary system, (Bi1-xSbx)2(Te1-ySey)3 with 0_??_x_??_1 and 0_??_y_??_1, were investigated by X-ray methods. 121 preparations were prepared by the direct reaction in a vacuum at 800°C from the molten state using the purest elementary substances, Bi, Sb, Te and Se each of 99.99% purity. The products were subjected to quenching by plunging them into water. X-ray observations show that the majority of the preparations belong to the rhombohedral system R3m and the rest belong to the orthorhombic system Pnma in addition to some which show to be a mixture of the two phases, both rhombohedral and orthorhombic. The lattice constants and densities and the ratios ρbulk/ρx-ray are measured for all the preparations. The lattice constants of the rhombohedral preparations, when expressed in the hexagonal unit cell aH and c, H, and the corresponding densities are found to be expressed by the following equations. aH(Å)=4.38-0.135x-0.23y cH(Å)=30.5+0.125x-1.7y ρH(g/cm3)=7.86-1.32x-0.12y-0.4xy These equations can be used to determine the compositions of the quaternary system, Bi-Sb-Te-Se with fair accuracy.