Thermal contraction phenomenon of cluster structure of indium melt
来源期刊:中国有色金属学报(英文版)2002年第3期
论文作者:程素娟 秦绪波 边秀房 孙民华 王忠华
文章页码:494 - 497
Key words:melt; cluster structure; thermal contraction; X-ray diffraction
Abstract: The structure of liquid indium was studied at 280, 390, 550, 650, 750℃, respectively, by using an elevated temperature X-ray diffractometer. The diffraction intensity, structure factor, pair distribution function, radial distribution function, nearest interatomic distance and coordinati on number were obtained. The results show that the structure of In melt can be approximately described by the random closed packed hard-sphere model with hard-sphere diameter d=2.86, packing density η=0.45. The cluster structure of In melt transforms from quasi-face-centered-cubic lattice into random closed packed structure above melting point. It has been found that the nearest interatomic distance r1 and coordination number Ns decrease with increasing temperature from 280℃ to 750℃, r1 decreases from 3.25 to 3.18 and Ns decreases from 12.771 to 6.648, and thermal contraction phenomenon of atom cluster occurs. Thermal contraction of In melt cluster is not homogeneous in whole measured temperature range. The sudden transformation and the biggest contraction have been found in the range of 390~550℃.