结构化学
結構化學
결구화학
CHINESE JOURNAL OF STRUCTURAL CHEMISTRY
2003年
1期
33-36
,共4页
杜记民%曾卉一%宋立军%董振超%马宏伟%郭国聪%黄锦顺
杜記民%曾卉一%宋立軍%董振超%馬宏偉%郭國聰%黃錦順
두기민%증훼일%송립군%동진초%마굉위%곽국총%황금순
pyrosilicate%crystal structure%barium%copper
A new phase of dibarium copper disilicate, B-Ba2CuSi2O7, was obtained by the solid-state reaction. Crystal data: Mr = 506.4, tetragonal, P21m, a = 8.284(2), c = 5.313(3) A。, V = 364.6(4) A。3, Z = 2, Dc = 4.61 g/cm3, ζ(MoK(a) = 0.71703 A。, μ = 13.91 mm-1, F(000) = 450 and T = 293(2) K; the final R = 0.0343, Wr = 0.0382 and S = 1.02 for 512 observed reflections (I > 3((I) refined by 34 variables. The compound was characterized by a layered structure composed of CuO4 tetrahedra and Si2O7 anions with the Ba cations filling the cavities between the layers. The building blocks of the present structure are similar to those in the a-Ba2CuSi2O7, but the linkage of CuO4 tetrahedra and Si2O7 anions is significantly different. In particular, the double-tetrahedral anions of Si2O76- form an orthogonal arrangement in the present structure, in contrast to the parallel arrangement reported in the a-Ba2CuSi2O7.
