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Mo_2(C_8H_8)_3是由Mo(CO)_6和环辛四烯在正癸烷中回流而制得。它的晶体属单斜晶系,空间群为P2_1,单胞参数为:a=7.772(3),b=11.964(5),c=10.445(2),β=100.33(2)°,V=955(1)~3,根据Z=2和fw=504.31计算密度Dc=1.75g/cm~3。在Enraf-Nonius CAD4衍射仪上用MoKα射线收集了I>2σ(I)的独立衍射点2393个。晶体结构用直接法(MULTAN)程序解出,所有非氢原子的位置参数和各向异性热振动参数经全矩阵最小二乘法修正,最后的偏离因子R_1(F)=0.030,R_2(F)=0.035。分子中钼—钼的距离为2.293(1),形成了Mo-Mo四重键。Mo_2(C_8H_8)_3存在两种晶型;一是与W_2(C_8H_8)_3同晶;另一是与Cr_2(C_8H_8)_3同晶。
Mo_2 (C_8H_8) _3 is prepared by refluxing Mo (CO) _6 and cyclooctatetraene in n-decane. Its crystal is monoclinic with a space group P2_1 with unit cell parameters of a = 7.772 (3), b = 11.964 (5), c = 10.445 (2), β = 100.33 955 (1) ~ 3, calculate the density Dc = 1.75g / cm ~ 3 according to Z = 2 and fw = 504.31. 2393 independent diffraction spots of I> 2σ (I) were collected on an Enraf-Nonius CAD4 diffractometer with MoKα radiation. The crystal structure was solved by the direct method (MULTAN). All the non-hydrogen atoms’ position parameters and the anisotropic thermal vibration parameters were corrected by full matrix least square method. The final deviation factor R_1 (F) = 0.030, R_2 (F) 0.035. Molecular molybdenum - molybdenum distance of 2.293 (1), forming a Mo-Mo quadruple bond. There are two crystal forms of Mo_2 (C_8H_8) _3; one is isomorphic with W_2 (C_8H_8) _3; the other is isomorphic with Cr_2 (C_8H_8) _3.