%A Dongxia Chen(陈冬霞), Qiang Sun(孙强), Zhanjun Yu(于占军), Mingyu Li(李明玉), Juan Guo(郭娟), Mingju Chao(晁明举), and Erjun Liang(梁二军)
%T Effects of W6+ occupying Sc3+ on the structure, vibration, and thermal expansion properties of scandium tungstate
%0 Journal Article
%D 2021
%J Chin. Phys. B
%R 10.1088/1674-1056/abd7d4
%P 66501-066501
%V 30
%N 6
%U {https://cpb.iphy.ac.cn/CN/abstract/article_123563.shtml}
%8 2021-05-18
%X We experimentally investigate effects of W6+ occupying the sites of Sc3+ in the unit cell of Sc2W3O12 (Sc8W12O48) on the structure, vibration and thermal expansion. The composition and structure of the doped sample (Sc6W2)W12O48±δ (with two W6+ occupying two sites of Sc3+ in the unit cell of Sc8W12O48) are analyzed and identified by combining the x-ray photoelectron spectroscopy and the synchronous x-ray diffraction with first-principles calculations based on density functional theory. Results show that the crystal with even W6+ occupying even Sc3+ in the unit cell is stable and maintains the orthorhombic structure at room temperature. The structure of the doped sample is similar to that of Sc2W3O12, and with even W occupying even positions of Sc in the unit cell and constituting the WO6 octahedra. Raman analyses show that the doped sample possesses stronger W-O bonds and wider Raman linewidths than those of Sc2W3O12. The sample doped with W also exhibits intrinsic negative thermal expansion in the measured range of 150 K-650 K.