Crystal structure and negative thermal ezpansion properties of solid solution Er2W3-zMozO12

摘要：

A series of solid solutions Er2W3-xMoxO12 (0.5≤x≤2.5) were successfully synthesized by the solid state method.Their crystal structures and negative thermal expansion properties were studied by high temperature X-ray powder diffraction and the Rietveld method.All samples with rare earth tungstates and molybdates crystallize in the same orthorhombic structure with space group Pnca,and show the negative thermal expansion phenomena related to transverse vibration of bridging oxygen atoms in the structure.Thermal expansion coefficients (TECs) of Er2W3-xMoxO12 were determined as-16.2×10-6 K-1 for x=0.5 and-16.5×10-6 K-1 for x=2.5 while-20.2×10-6 K-1 and-18.4×10-6 K-1 for unsubstituted Er2W3O12 and Er2Mo3O12 in the identical temperature range of 200-800 ℃.High temperature XRD data and bond length analysis suggest that the difference between W-O and Mo-O is responsible for the change of TECs after the element substitution in the series of solid solutions.

关键词： negative thermal ezpansion X-ray diffraction rare earth molybdate tungstate

作者: PENG Jie LIU Xin-zhi GUO Fu-li HAN Song-bai LIU Yun-tao CHEN Dong-feng ZHAO Xin-hua HU Zhong-bo

作者单位: Experimental Physics Center,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100 China Institute of Atomic Energy,Beijing 102413,China College of Chemistry,Beijing Normal University,Beijing 100875,China College of Chemistry and Chemical Engineering,Graduate University of the Chinese Academy of Sciences

会议类型: 国际会议

会议名称: 2009 Frontier Symposium of China Postductors on Materrials Science(2009年中国博士后材料科学前言论坛)

会议地点: 长沙

会议语种:英文

页码: 1623-1627

在线出版日期: 2009-11-22（万方平台首次上网日期，不代表论文的发表时间）