MOLECULAR AND CRYSTAL STRUCTURES OF TETRANUCLEAR MOLYBDENUM CLUSTER[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)~6]■

The new cluster[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)_6]has been prepared by thereaction of molybdenum pentachloride and o-methylbenzoic acid.The crystal andmolecular structures were determined by the X-ray diffraction method.It crystallizesin the orthorhombic space group Pnna with cell parameters:Mr=1361.6,a=13.792(4),b=17.957(3),c=20.974(9) ,V=5194(2) ~3,Z=4,Dc=1.74/cm~3,F(OOO)=2704,μ(MoK )=11.0/cm,R=0.074.     

CRYSTAL AND MOLECULAR STRUCTURE OF TETRANUCLEAR MOLYBDENUM CLUSTER Mo_4(μ_3-O)_2Cl_2(o-CH_3C_6H_4COO)_6

<正> Cluster compound [Mo4(μ3-O)2O4Cl2(o-CH3C6H4COO)6] has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid. It crystllizes in the orthorhombic space group Praia with cell parameters:Mr= 1361. 6,a=13. 792(4), b=17. 957(3),c= 20. 974(9) A ,V=5194(2) A3,Z= 4,Dc= 1. 74g/cm3,F(000) = 2704,μ(MoKa) = 11. 0/cm. The final R=0. 061 and Rw=0. 064 for 1441(I>3oooooooooo(I)) observed unique reflections. The tetranuclear complex molecule, where the molybdenum atoms are bridged by two μ3-O atoms and six bidentate o-methylbenzoato ligands,is located at crystallographic two-fold axis(x,-1/4,1/4) with one Mo-Mo bond of 2. 610A     

Mo_4(μ_3-O)_2O_4Cl_2(O_2CC_6H_5)_6和Mo_4(μ_3-O)_2O_4Cl_2(O_2CC_6H_4CH_3)_6·2C_6H_5Cl簇合物中弱M—M键的研究

测定了Mo_4(μ_(3-)O)_2O_4Cl_2(O_2CC_6H_5)_6和Mo_4(μ_(3-)O)_2O_4Cl_2(O_2CC_6H_4CH_3)_6·2C_6H_5Cl四钼簇合物在N,N-二甲基甲酰胺溶液中的循环伏安特性、电子吸收光谱、固体粉末样品的表面光电压谱和光声光谱。讨论Mo_2(V)结构单元中弱M—M键的特性,认定了Mo—Mo键前线区域轨道的对称标号。     

四钼簇合物Mo_4(μ_3—O)_2O_4Cl_2(OCOC_6H_5)_6和[Mo_4(μ_3—O)_2O_4Cl_2(OCOC_6H_4CH_3)_6]·2C_6H_5Cl的合成、结构、反应机理及光谱性质研究

用MoCl_5和C_ 6H_5COOH(或CH_3C6H_4COOH)在氯苯溶液中反应,得到四钼簇合物Mo_4(μ_3-O)_2O_4Cl_2-(OCOC_6H_5)_6(或[Mo_4(μ_3-O)_2O_4Cl_2(OCOC_6H_4CH_3)_6]·2C_6H_5Cl)晶体。用X射线单晶衍射法测定了簇合物的晶体结构,运用18电子规则及簇合物的晶体结构数据,得到金属Mo-Mo键键价为1,钼在簇合物中均呈+5价。进行了反应机理的探讨,簇合物中端基氧和桥基氧的存在来自于苯甲酸(对甲基苯甲酸),MoCl_5和C_6H_5COOH(CH_3C_6H_4COOH)作用时,首先生成钼的含氧配合物MoOCl_3,然后生成双核钼配合物Mo_2(μ_2-O)_2O_2Cl_2,进一步形成配合物。红外光谱、激光拉曼光谱和磁化率的测定证明了结构分析的结果。值得注意的是,固体表面光电压谱和固体光声光谱的测定,簇合物Mo_4(μ_3-O)_2O_4Cl_2(OCOC_6H_5)_6的表面光电压谱在～600nm处有一光致电荷分离谱带。     

四钼簇合物[Mo4O4Cl2(μ3-O)2(o-CH3C6H4COO)6]性质与电子结构研究

UV spectra, IR spectra, Electronic oxidation-reduction properties and XPS spectrum of the tetramolybdenum cluster Mo_4O_4Cl_2(μ_3-O) (o-CH_3C_6H_4COO)_6 has been studied, and the electronic structure of the cluster has been interpreted with semiempirical quantum chemical calculation based on EHMO.     

CRYSTAL STRUCTURE OF (Et_4N)2 [Mo_3 (μ_3-O) (μ_3-Cl) (μ-Cl)_3 Cl_6]·EtOH

<正> Mr=963.9, monoclinic, P21/c, a=11.379(3), b=20.766(2), c=14.487(3) A,β=91.49(2)°, V=3518.9A3, Z=4, Dm=1.81, Dx=1.819 g·cm-3, MoKα radiation, λ=0.71073A, μ=18.167, F(000)=1916, T=293 K, R=0.040 for 3261 reflections. The structure consists of two sets of tetraethylammonium cations and trinuclear Mo cluster anions. The cluster skeleton is formed by three Mo atoms arranged in an isosceles triangle with a Cl and an O atoms as capping ligands.     

一种二帽pseudo-Keggin结构簇合物[HN(C_2H_5)_3]_3[N(C_2H_5)_3]_2[Mo_8~ⅣMo_4~ⅤV_2~ⅣO_(38)(PO_4)]的水热合成、结构和性质研究

金属－氧簇合物因其结构多样性及在催化、材料和医药等方面的应用而引起人们的关注犤１犦。在众多金属－氧簇合物中，Keggin结构及金属取代Keggin结构金属－氧簇被大量报道，但由于很难获得高质量单晶，有关二帽Keggin结构的报道非常少，目前只有几例报道犤２～９犦。近年来，随着水热法应用到金属－氧簇的合成，陆续获得了一系列具有新颖结构的簇合物。１９９８年，通过水热法获得了第一个二帽pseudo－Keggin结构簇合物犤NH４犦４H犤PMo８VⅣ４VⅤ２O４２犦·２４H２O犤１０犦。我们用水热法以三乙胺做模板剂获得了一种全新的二帽pse…     

四核银簇合物Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4与二核铜化合物Cu_2(o-CH_3C_6H_4CSS_2)_2(Py)_2的合成和晶体结构

邻甲基苯荒酸四乙基铵盐分别与硝酸银和氯化铜反应,经毗啶重结晶,得到四核银簇合物Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4(晶体Ⅰ)和二核铜化合物Cu_2(o-CH_3-C_6H_4CSS_2)_2(Py)_(晶体Ⅱ)。用X射线单晶衍射法测定了它们的晶体结构。晶体Ⅰ的空间群为P2/n。晶胞参数:a=14.757(4),b=12.231(3),c=15.183(4)A,β=91.14(2)°,V=2739.95A~3,Z=2。2590个衍射点参与修正,最终偏差因子R=0.087。晶体Ⅱ的空间群为C_1~1-P1。晶胞参数:a=9.307(7),b=9.546(7),c=10.119(8)A,α=95.06(9),β=109.74(10),γ=118.86(10)°,V=705.94A~3,Z=1。1198个衍射点参与修正,最终偏差因子R=0.086。 Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4分子中Ag_4呈蝴蝶状构型,其配位情况与四核银簇合物Ag_4(a-C_(10)H_7CS_2)_4(Py)_4相似。Cu_2(o-CH_3C_6H_4CSS_2)_2(Py)_2分子构型与Cu_2(a-C_(10)H_7CSS_2)_2(Py)_2十分相似。Cu—Cu键长为2.608A。而且邻甲基苯荒酸与Cu~(2+)反应包括一个氧化还原反应,也与a-萘荒酸与Cu~(2+)反应相似。可以认为邻甲基苯荒酸与a-萘荒酸有相似的空间效应和电子效应。     

(Me_4N)[Mo_3(μ_3-O)(μ-Cl)_3(μ-O_2CCH_2Cl)_3Cl_3]三核钼簇合物的合成、结构及电化学研究

本文测定了三核钼簇合物（Ｍｅ４Ｎ）［Ｍｏ３（μ３Ｏ）（μＣｌ）３（μＯ２ＣＣＨ２Ｃｌ）３Ｃｌ３］的晶体结构，该晶体属于正交晶系，空间群Ｐ２１２１２１，晶胞参数：ａ＝１２．６３７５（９），ｂ＝１８．８９４（４），ｃ＝１０．７３３（４），Ｍｒ＝８７１．１５，Ｚ＝４，Ｄｏ＝２．２６ｇ／ｃｍ３。晶体属离子型，其簇阴离子是由一个μ３Ｏ原子桥连于准等边三角形排布的三核钼簇骼构成，具有接近Ｃ３Ｖ的对称性。其中ＭｏＭｏ和Ｍｏ（μ３Ｏ）平均键长分别为２５７７和１９８０。同时利用循环伏安法测定了该簇合物在ＣＨ３ＣＮ溶剂中的氧化还原电位。     

SYNTHESIS AND CRYSTAL STRUCTURE OF Mo_3(μ_3-O)(μ-S)_3[S_2P(OEt)_2]_4(C_3H_3N_2)

<正> Mr=1164, space group C2/c, a=14.954(13)A,b=22.323(6)A,c=27.003(18)A,β=98.23(7)°,V=8920 A3, Z=8. Final R=0.069 for 2818 unique diffraction data with I≥30(I). The title cluster compound is of Ml configuration with a triple bridging atom O and with a 'loosely coordinated site' occupied by an imidazole ligand. Three Mo-Mo bond lengths are 2.657 (2), 2.649(2),and 2.646(2)A,respectively. The average bond length of Mo-(μ3-O) bonds is 2.052 A.     

CRYSTAL STRUCTURE AND REACTIVITY OF (Et_4N) [Mo_3(μ_6-O)-(μ-Cl)_3(μ-OAc)_3Cl_3]

<正> (Et4N)[Mo3(μ3-O)(μ-Cl)3(μ-OAc)3Cl3], C14H29Cl6Mo3NO7, Mr = 823.92, triclinic, P1, a = 17. 508(4), b = 19. 602(3), c=8. 091(2)A, α=91. 25(2)°, β= 96. 56(2)°,γ= 83. 61(2)°, V = 2741(1)A3, Z = 4, Dc = 2.00g/cm3, MoKa (λ=0. 71069A), μ= 19. 44cm-1, F(000) = 1616, T = 23℃, final R = 0. 055, Rw = 0. 068 for 5728 unique intensity data (I≥3σ(I)).The molecule consists of cluster aniorn [Mo3(μ3-O) (μ-Cl)3(μ-OAc)3Cl3]- and cation (Et4N) + . There are two independent molecules in an asymmetric unit whose cluster anions A and B have the same configuration except for some bonding parameters. The cluster core may be described as an equilateral {Mo3} triangle with a capping O atom and three bridging Cl atoms below and above it respectively. In addition, each pair of Mo atoms is bridged by an acetate group and each Mo atom is further coordinated to a terminal chlorine atom. The three Mo - Mo bonds are 2. 587 (2), 2.587(2), 2. 582(2) A for cluster anion A and 2. 587(2), 2.595(2), 2.577 (2) A for cluster a     

含硫桥过渡金属簇合物的结构化学研究——(C_5H_7S_2)_3[Mo_3(μ_3-S)_2(μ_2-Cl)_3 Cl_6]的晶体与分子结构

本文所研究的化合物系黑色准八面体晶体。晶体的空间群为I4_1/a;晶胞参数:a-22.885(10),c=25.407(7)。ρ_(obs)=2.07克/厘米~3,P_(calc)=2.126克/厘米~3。在CAD-4四圆衍射仪上,用MoK_α射线收集到I≥3σ的1621个独立衍射点的衍射强度数据。晶体结构借助三维Patterson函数解出,最小二乘方精修,偏离因子R=0.056。结果表明,晶体结构由三核钼簇阴离子和围绕着它的三个平面状阳离子构成。阴离子中,三个钼原子由两个μ_3-S桥和三个μ_2-Cl桥联结在一起,每个Mo原子另外再和两个Cl原子配位。如果撇开Mo-Mo之间的作用,则每个Mo原子周围的配位体可看成八面体排布。然而,化合物的反磁性及Mo-Mo原子间距(2.55,2.64,2.65)都显示出Mo-Mo键的特征。     

羧基配位的三核钼簇合物的研究-[(NH_2)_2CSH~+][Mo_3(μ_3-O)(μ_Cl)_3(μ-O_2CH)_3Cl_3]的合成和结构

报道了Mo_3簇合物[(NH_2)_2CSH][Mo_3O(O_2CH)_3Cl_8]的合成和X射线晶体结构。讨论了双齿配体RCO_2~-在Mo_3簇合物中只成桥,偶或成单齿端基而不成螫合配位的特征,此外,提出了含羧、单帽Mo_3簇合物的通式,并讨论了其中几种典型簇式的簇合物合成研究的可能性     

CRYSTAL STRUCTURE OF (Et_4N)_2[Mo_6O(μ-O)_(12)O_5]

<正> Mr= 1140.4, tetragonal,P4/mnc,a=10.726(2), c=14.208(3)A, Z=2,Dc=2.316 g.cm-3,V=1634.5(9)A3,final R=0.050 for 1457 independent reflections. The anion [Mo6O19]2- has its No atoas in octahedral configuration with one oxygen atom situated in the center of the octahedron, twelve bridging oxygen atoms,and six terminal oxygen atoms. The average bond lengths of the three types of Mo-O bonds are 1.678 A (Mo=0), 1.919A [Mo-(μ-O)], and 2.310 A [Mo-(μs-O)], respectively.     

CRYSTAL STRUCTURE OF (C_5H_9C_5H_4)_3Er_4(μ_2-Cl)_6(μ_3-Cl)(μ_4-O)-(THF)_3

<正> The crystal of (C5H9C5H4)Er4(μ2-Cl)6(μ3-Cl)(μ4-O)(THF)3 belongs to triclinic space group P1, with a = 11. 909(4), b = 15.343(5), c=15. 619 (4)(?), α=104. 18(2), β=98. 81(3), γ= 111. 06(2)°, V = 2486(1)(?)3, Z = 2, Dc = 2. 07g/cm3, λ(MoKα) = 0.71073(?), μ= 73. 4cm-1, F(000) = 1476, Mr=1549. 25. The structure was solved by Patterson and Fourier techniques and refined by block diagonel least-squares method to final R = 0. 078 and Rw = 0. 084 for 5594 reflections with I≥1. 5σ(I). The results revealed that the complex is composed of four Er atoms bridged by seven Cl and one oxygen atoms with three of the Er atoms bonded each to a cyclopentylcyclopentadienyl group, and one Er atom, bonded to three THF. The Er atoms constitute a pseudo-tetrahedron.     

两个具有松散配位的三核钼簇合物{Mo_3(μ_3—S)(μ—S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}·CH_3CN(Ⅰ){Mo_3(μ_3—O)(μ—S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}(Ⅱ)的合成和晶体结构

本文报道了两个具有松散配位的三核钼簇合物{Mo_3(μ_3—S)(μ—S)_3[S_2P(OEt)_2]_4·(C_3H_3ON)}·CH_3GN(Ⅰ)、{Mo_3(μ_3—O)(μ—S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}(Ⅱ)的合成和晶体结构。簇合物(Ⅰ)属单斜晶系,空间群为P2_2/n,晶胞参数为a=16.579(3),b=16.959(2),c=16.867(2);β=94.44(1)°;v=4728 3;Z=4;D_c=1.778g·cm~(-3),用Patterson法解出结构,最终偏离因子R=0.045。簇合物(Ⅱ)属三斜晶系,空间群为P1,晶胞参数为a=13.175(4),b=13.372(6),c=16.656(3);α=117.87(4)°,β=60.09(3)°,γ=109.03(3)°;ν=2231 3;Z=2;D_c=1.798g·cm~(-3),用直接法解出结构,最终偏离因子R=0.066。两个簇合物均为以具有一个松散配位为特征的单帽三核簇,而且松散配位上均被一嘿唑五员环所占据,其主要差别在于簇合物(Ⅰ)的簇胳为Mo_3S_4,而簇合物(Ⅱ)则为一Mo_3OS_3·文中对这一“松散”配位的三核钼簇合物的活泼性进行了讨论。     

双核配合物组合合成Mo_nFe_(4-n)S_4单立方烷簇合物及Mo_2Fe_2S_4(C_4H_8dtc)_6·3.5C_2H_2Cl_4的结构

从含有M Fe(M=Mo,Fe)结构单元的双核配合物Mg(DMF)_6[Fe_2S_2Cl_4]及Mg(DMF)_6[FeCl_2·MoS_4]起始,经不同的组合反应,分别得到Fe_4S_4,MoFe_3S_4及Mo_2Fe_2S_4单立方烷簇合物。讨论了这一反应的某些特点并报道了双桥联六配体的Mo_2Fe_2S_4(C_4H_8dtc)_6的晶体与分子结构。     

有机锡氧簇合物[(μ-O)(μ-OH)Sn_2(n-Bu)_4]_2(C_5H_4NCO_2)_2的合成、结构和量子化学研究

吡啶-4-甲酸与(n-Bu)2SnO反应合成二(μ-氧)二(μ-羟基氧)桥联四[二(正丁基)锡]二(吡啶-4-甲酸酯),经元素分析、1H NMR、IR和X-射线衍射表征分子结构,该配合物晶体属单斜晶系,空间群P21/n,晶胞参数:a=1.306 5(3)nm,b=1.314 5(2)nm,c=1.660 8(3)nm,β=96.180(5)°,V=2.835 7(9)nm3,Z=4,Dc=1.454 g.cm-3,μ(Mo Kα)=1.784 mm-1,F(000)=1 248,R1=0.044 9,wR2=0.124 1(I2σ(I))和R1=0.088 7,wR2=0.175 6(对所有的衍射)。共收集15 802个衍射点,其中独立衍射点4 885个,可观察衍射(I2σ(I))点2 733个用于结构精修。中心Sn原子形成五配位畸变三角双锥构型,分子间通过N…H-O氢键作用形成二维网络结构。利用量子化学G98W软件,在Lanl2dz基组对配合物的稳定性、前沿分子轨道组成及能量进行研究。     

三核钼簇合物H[H_2O]_3[Mo_3O(OAc)l_3Cl_6]的合成,分子结构及红外光谱归属的研究

本文报道MoCl_3·3H_2O与乙酸作用生成三核钼簇合物H[H_O]_3[Mo_3O(OAc)_3Cl_6]的反应,并用X射线单晶结构分析方法测定了簇合物的晶体结构,结晶学参数为:α=17.468(4),b=9.948(2),c=13.035(2)A.β=148.83(2)°,V=1172(1)A~3,Z=2,D_(?)=2.109g/cm~3.空间群为Pc.非权重偏离因子是R=0.057.结构分析结果表明该化合物阴离子为单氧帽等边三角形三核钼簇合阴离子,Mo—Mo平均距离2.569A.对簇骼单元[Mo_3O(μ-Cl)_3Cl_3]~(2+)进行简正坐标分析.从理论上对振动光谱谱带进行了归属.10条IR谱带的观测和计算频率的平均偏差为1.15％.本文讨论了特征谱带(包括金属键)的归属和力常数的合理性.