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本文报道了含双端氧配位的Mo—Fe—S原子簇化合物[Fe(MoS_4O)_2][N(C_2H_5)_4]_3的合成、晶体结构和分子结构。该化合物的晶体属单斜晶系,P2_1/n空间群,晶胞参数为:a=13.019(4),b=16.959(5),c=18.234(5),β=97.34(2)(°),z=4。最终一致性因子为:R=0.0740,R_w=0.0598。该化合物中的Mo—S_t端键和Mo—S_b桥键比不合端氧配位的相应化合物Mo—S键长长得多,可能是由于Mo的价态降低和氧的电负性比硫大得多,氧对Mo的配位使s→→O发生电荷转移的缘故。 相似文献
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松柏烯是从红松树中提取和分离出来的一种天然有机物。它是白色针状结晶,晶体属于P2_12_12_1空间群,其晶体学参数:α=6.243(1),b=13.886(6),c=21.650(7),V=1876.96(11)A,Z=4,R=0.0716.松柏烯是一种十四元环二帖烃化合物,即1-异丙基-4,8,12-三甲基-2,4,7,11-十四元环四烯。 相似文献
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本文用HMO理论(采用图论方法)计算了单核、双核和三核分子氮络合物的稳定化能量,电荷密度及键序,得到了下列结论:(1)对于单核和双核分子氮络合物,端基配位比侧基配位稳定,而三核分子氮络合物,在相当宽的能量参数变化范围内,兼有端、侧基配位比只含有端基配位稳定.(2)端点氮原子比中间氮原子带有更多的负电荷.(3)络合物中过渡金属原子的d轨道能级越高,d电子数越多.则氮原子上带的负电荷越多. 相似文献
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在这篇文章中,我们报道了一种具有生物组合活性的固氮酶活性中心模型化合物的合成、光谱性质、催化活性和生物组合性质。以KBH4为还原剂,该化合物的乙炔还原活性达11.11nM产物/nM·Mo·分钟,对乙烯的选择性为74.8%。15N标记实验表明,它具有一定周氮活性。与柱分离的缺辅基钼铁蛋白组合加铁蛋白,乙炔还原活性高达38.21nM乙烯/nMMo分钟,相当于天然FeMo-co活性的9%。缺辅基钼铁蛋白与模型化合物组合聚丙烯酰胺凝胶电泳迁移率比组合前更加接近正常钼铁蛋白的电泳迁移率。 相似文献
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By mixing appropriate quantity of FeCl_2, (NH_4)_2MoS_4 ano HSCH_2CH_2OH in MeOH--MeONa, the crystal [(C_2H_5)_4N]_4[Fe_6S_9(SCH_2CH_2OH)Cl] was obtained. The cluster compound crystallizes in triclinic, space gtoup, P1, and crystal cell constants:a = 12.818(4)A, b = 13.632(3)A, c = 18.328(7)A, α = 106.09(2)°, β = 100.75(2)°, γ = 102.69(2)°, Z = 2. On the basis of 7517 unique data (I>3σ(I)) the structure has been refined toR = 0.0818 by the block-diagonal least-squares. The result of structure analysis shows thatthe cluster compound [Fe_6S_9(SCH_2CH_2OH)CI]~(4-) includes doubly bridging μ_2-S, triply bridgingμ_3-S and quadruply bridging μ_4-S. The [Fe_6S_9]~(2-) core of [Fe_6S_9(SCH_2CH_2OH)CI]~(4-) consistsof eight nonplanar Fe_2S_3 rhombs that are fused edge-sharing to give four Fe(μ_2-S)(μ_3-S)Fe,two Fe(μ_2--S)(μ_4-S)Fe and two Fe(μ_3-S) (μ_4-S)Fe subunits. The quantum chemical calcu-lation of EHMO method was carried out for this cluster compound. The structure analysisgives a rule wit 相似文献
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采用表面沉积法制备HDPE/NiS和HDPE/Fe_xS复合材料.用扫描电子显微镜、X光电子能谱、光电流光谱、穆斯堡尔谱等方法对其表面形貌和组成进行了表征。经测量HDPE/NiS表面电阻率可达10 ̄1Ω左右;HDPE/Fe_xS表面电阻率可小至10 ̄2Ω左右。 相似文献
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[Fe(MoS_4O)_2] [N(C_2H_3)_4]_3 cluster compound with di-end-oxygen ligands has been prepared and characterized by the X-ray diffraction method. The compound crystallizes in a monoclinic space group P2_1/n with lattice parameters a=13.019(4), b=16.959(5), c=18.234(5), β=97.34(2)(°), Z=4. The final agreement factors are R=0.0740, Rw=0.0598. The terminal bond length, Mo-S_t and bridged one, MO-S_b for the compound are much longer than the counterpart without end-oxygen ligand. It possibly suggests that low valence of molybdenum and smaller electronegativity of sulphur than oxygen lead to the charge transfer as S→Mo→O. 相似文献
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