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ｃｉｓ－Ｍｏ（ｄｍｆ）_３Ｂｒ_３（ｄｍｆ指Ｎ，Ｎ－二甲基甲酰胺）的晶体结构已经用三维衍射数据测定，数据是在Ｎｏｎｉｕｓ ＣＡＤ—４ Ｘ射线衍射仪上以ＭｏＫａ射线收集的．空间群为Ｐ２１／ｎ．晶胞中含有四个分子．晶胞参数为：ａ＝１２．７２０（３）Ａ，ｂ＝１２．１２４（７）Ａ，ｃ＝１１．７２２（３）Ａ，β＝９２．７３（２）°．按Ｚ＝４，密度计算值为２．０４７ｇ／ａｍ３，而测量值为２．０４ｇ／ｃｍ３．从１０７７个Ｉ＞３σ的独立衍射点，解出了晶体结构并精修到最终的Ｒ值０．０４０．在每个分子中，三个Ｂｒ原子和三个ｄｍｆ分子中的Ｏ原子围绕着Ｍｏ原子形成了八面体并按顺式构型排布．八面体中的各原子间距为：Ｍｏ—Ｂｒ，２．５６６（２），２．５５８（２），２．５５７（２）Ａ和Ｍｏ－Ｏ（ｄｍｆ）２．１１７（１０），２．１２３（９）．２．１４２（１０）Ａ°
The crystal structure of cis-Mo (dmf) _3Br_3 (dmf refers to N, N-dimethylformamide) has been determined with three-dimensional diffraction data collected on a Nonius CAD-4 X-ray diffractometer with MoKa rays. The space group is P21 / n. The unit cell contains four molecules. The unit cell parameters are: a = 12.720 (3) A, b = 12.124 (7) A, c = 11.722 (3) A, β = 92.73 (2) °. Press Z = 4, the density calculated is 2.047 g / am3, and the measured value is 2.04 g / cm3. From 1077 independent diffraction points with I> 3σ, the crystal structure was solved and refined to a final R value of 0.040. In each molecule, the O atoms of the three Br atoms and the three dmf molecules form an octahedron around the Mo atom and are arranged in a cis configuration. The atomic distances in the octahedron are: Mo-Br, 2.566 (2), 2.558 (2), 2.557 (2) A and Mo-O (dmf) 2.117 (10), 2. 123 (9). 2.142 (10) A °