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X光晶体结构分析证实H_(3+n)[AsMo_(12-n)V_+nO_(40)]·9H_2)(n=2—4)的晶体同构,空间群为P,Z=2。n=2时,a=13.951(5),b=14.137(5),c=13.556(4),α=112.44(2),β=109.49(3),γ=60.77(3)°,V=2120.2,M_r=1943.36,D_c=3.044g.cm~(-3),μ=40.90cm~(-1),F(000)=1828。用6216个I>3σ(I)的独立衍射精修结构,R=0.082;n=3时,a=13.891(7),b=14.076(5),c=13.483(5)A,α=112.34(3),α=109.26(3),γ=60.82(3)°,V=2094.5,M_r=1899.37,D_c=3.011g.cm~(-3),μ=40.63cm~(-1),F(000)=1792。用6699个I>3σ(I)的独立衍射精修结构,R=0.054;n=4时,a=13.854(3),b=14.099(2),c=13.501(4),α=112.09(2),β=109.13(2),γ=61.03(2)°,V=2103.0,M_r=1855.38,D_c=2.92(悬浮法),D_c=2.930g.cm~(-3),μ=39.71cm~(-1),F(000)=1756。用7613个I>3σ(I)的独立衍射精修结构,R=0.044。实验采用MoKα辐射,λ=0.71073,T=296K。杂多阴离子均呈准Keggin结构,12个金属原子呈无序分布,可以M(Mo/V)表示。AsO_4四面体中As—O键长1.66—1.68,O—As—O键角均在109.5°左右。畸变的MO_6八面体中,M—O键长分布在1.63—2.36范围。水分子无序处在晶胞中十四个位置上,除O_w(12)和O_w(13)外的水分子均与杂多阴离子形成氢键,且水分子间形成如沸石中那样的复杂?
X-ray crystal structure analysis confirmed the crystal isomorphism of H_ (3 + n) [AsMo_ (12-n) V_ + nO_ (40)] · 9H_2) (n = 2-4) a = 13.951 (5), b = 14.137 (5), c = 13.556 (4), α = 112.44 (2), β = 109.49 (3), γ = 60.77 (3) ° for n = 2120.2, M_r = 1943.36, D_c = 3.044g.cm -3, μ = 40.90cm -1, F000 = 1828. R = 0.082; n = 3, a = 13.891 (7), b = 14.076 (5), c = 13.483 (5) A, α = 112.34 with 6216 I <3σ (I) (3), α = 109.26 (3), γ = 60.82 (3) °, V = 2094.5, M_r = 1899.37, D_c = 3.011g.cm -3, μ = 40.63cm -1, F (000) = 1792. R = 0.054 for n = 4, a = 13.854 (3), b = 14.099 (2), c = 13.501 (4) and a = 112.09 for the refined structure with 6699 I <3σ (I) 2 = β = 109.13 2 γ = 61.03 2 ° V = 2103.0 M_r = 1855.38 Dc = 2.92 (suspension method) Dc = 2.930g.cm -3 μ = 39.71 cm ~ (-1), F (000) = 1756. The structure was refined with 7613 independent diffraction with I> 3σ (I), R = 0.044. Experiments using MoKα radiation, λ = 0.71073, T = 296K. Heteropolyanions are quasi-Keggin structure, 12 metal atoms were disordered distribution, which can M (Mo / V) said. AsO_4 tetrahedra As-O bond length 1.66-1.68, O-As-O bond angle is about 109.5 °. In the distorted MO_6 octahedron, the M-O bond length distribution is in the range of 1.63-2.36. Water molecules are disordered in fourteen positions in the unit cell. All water molecules other than O_w (12) and O_w (13) form hydrogen bonds with heteropolyanions, and the water molecules become complex as zeolite.