Crystal Structure of La_4V_5Si_4O_(22)──A Mixed-Valence Lanthanum Vanadium (Ⅲ/Ⅳ) Oxosilicate  

作　　者：陈久桐 黄锦顺 等 

机构地区：[1]StateKeyLaboratoryofStructuralChemistry,FujianInst [2]StateKeyLaboratoryofStructura

出　　处：《Chinese Journal of Structural Chemistry》1995年第4期314-317,共4页结构化学（英文）

摘　　要：The title compound was prepared by solid state reaction of LaCl_3/V inan evacuated silica tube where the silicon came from the reaction tube. The compoundcrystallizes in monoclinic space group C2/m with cell dimensions of a=13. 482 (7), b=5. 604(3), c=11. 091(3) A, β=100. 44(3)°, V=824(1) A3, Mr= 1274. 66 , Dc=5. 14 g/cm3, F(000) = 1150, μ- 13. 20 mm-1 and Z=2; final R=0. 061, Rw=0. 054for 1037 observed reflections (Ⅰ>3σ(Ⅰ) ) . It is isostructural with quasi-ZD Pr_4V_5Si_4O_(22)compound with the Ⅴ-Ⅴ distances across the shared VO6 octahedral edges of 2. 802 Aand vanadium ions show mixed-valence(Ⅲ/Ⅳ) with an average value of+ 3. 2.The title compound was prepared by solid state reaction of LaCl_3/V inan evacuated silica tube where the silicon came from the reaction tube. The compoundcrystallizes in monoclinic space group C2/m with cell dimensions of a=13. 482 (7), b=5. 604(3), c=11. 091(3) A, β=100. 44(3)°, V=824(1) A3, Mr= 1274. 66 , Dc=5. 14 g/cm3, F(000) = 1150, μ- 13. 20 mm-1 and Z=2; final R=0. 061, Rw=0. 054for 1037 observed reflections (Ⅰ>3σ(Ⅰ) ) . It is isostructural with quasi-ZD Pr_4V_5Si_4O_(22)compound with the Ⅴ-Ⅴ distances across the shared VO6 octahedral edges of 2. 802 Aand vanadium ions show mixed-valence(Ⅲ/Ⅳ) with an average value of+ 3. 2.

关 键 词：lanthanum vanadium oxosilicate crystal structure MIXED-VALENCE 

分 类 号：O614.331.66[理学—无机化学] O614.511[理学—化学]