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(Me_4N)[Mo_3(μ_3-O)(μ-Br)_3(μ-O_2CH)_3Cl_3)晶体是在介质HCl-EtOH中,通过MoBr_3、甲酸和Me_4NBr进行反应制得。由X射线单晶结构分析,空间群为P_1,晶胞参数:a=6.848(1),b=11.933(1),c=13.164(1)(?),α=100.20(1),β=93.12(1),γ=104.14(1)(°);z=2;D_(obs).=2.72gcm~(-3),D_(calc).=2.76gcm~(-3)。研究表明,晶体属离子型,由(Me_4N)~+阳离子和簇阴离子 [Mo_3(μ_3-O)(μ-Br)_3(μ-O_2CH)_3Cl_3]~- 组成。簇阴离子中,μ_3-O原子桥联以等边三角形排布的三核钼簇胳,成为单氧帽钼簇阴离子。每对钼原子间另有—(μ-O_2CH)基和一个Br原子作双向桥配体,此外,每个钼原子又有一端基Cl原子配位,使得在每个Mo原子周围形成畸变八面体构型。整个簇阴离子具近似C_(3V)对称性。
(Me_4N) [Mo_3 (μ_3-O) (μ-Br) _3 (μ-O_2CH) _3Cl_3) is prepared by the reaction of MoBr_3, formic acid and Me_4NBr in medium HCl-EtOH. According to the X-ray single crystal structure analysis, the space group is P_1, the unit cell parameters are: a = 6.848 (1), b = 11.933 (1), c = 13.164 (1) 93.12 (1), γ = 104.14 (1) (°); z = 2; D obs. = 2.72gcm -3, D calc. = 2.76gcm -3. The results show that the crystal is of ionic type and consists of (Me_4N) ~ + cation and cluster anion [Mo_3 (μ_3-O) (μ-Br) _3 (μ-O_2CH) _3Cl_3] Cluster anions, μ_3-O atoms bridged equilateral triangular arrangement of tri-nuclear molybdenum cluster, a monobasic molybdenum anions. In each pair of molybdenum atoms there is another - (μ-O 2 CH) group and a Br atom as a bi-bridging ligand. In addition, each molybdenum atom has an end-group Cl atom coordinated so that a distorted octahedron is formed around each Mo atom structure. The entire cluster anions with similar C_ (3V) symmetry.