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RbIO_3·2HIO_3的晶体结构用重原子法解得并作了修正。晶体属三斜晶系,晶胞参数a=8.332,b=8.232,c=8.264;a=60.66°,β=85.80°,γ=66.10°.晶胞中含化学式数x=2.测量密度D_m =4.61g cm~(-3)。实验和分析结果表明,结构为非中心对称,即晶体属P1空间群,但具有高中心对称度,作为中心对称度的一种量度<|△r|>w=0.09.并得到倍频效应的印证。偏离因子R=0.076.每个碘原子同三个最近邻氧原子成共价键,平均键长约为1.8,形成一个畸变的10_3~-三角锥;此外还同三个次近邻氧原子以2.5-3.3的距离结合,这六个氧原子形成一个畸变的八面体,碘原予位于其中心。每个铷原子与邻近九个氧原子以2.86-3.5的距离结合,形成RbO_9多面体。
The crystal structure of RbIO_3 · 2HIO_3 was solved by heavy atom method and corrected. The crystal belongs to the triclinic system with unit cell parameters a = 8.332, b = 8.232, c = 8.264, a = 60.66 °, β = 85.80 °, γ = 66.10 °. The measurement density Dm = 4.61g cm ~ (-3). The experimental and analytical results show that the structure is non-centrosymmetric, that is, the crystal belongs to the P1 space group, but has a high degree of centrosymmetry as a measure of central symmetry <| Δr |> w = 0.09. The proof. The deviation factor is R = 0.076. Each iodine atom is covalent with three nearest oxygen atoms with an average bond length of about 1.8 , forming a distorted 10_3 ~ -triangular pyramid. In addition, 2.5-3.3 distance combination, the six oxygen atoms form a distorted octahedron, Iodine is located in the center. Each rubidium atom is bound to nine adjacent oxygen atoms at a distance of 2.86-3.5 cm to form an RbO9 polyhedron.