三核钼原子簇化合物研究——Mo_3(μ_3-S)(μ_2-S_2)_3[S_2P(OEt)_2]_3Cl的晶体与分子结构

本文所研究的化合物为草黄色晶体,属三斜晶系,空间群为P1;晶胞参数:a=11.570(2)A,b=13.093(1)A,c=14.399(2)A,a=102.62(1)°,β=102.15(1)°,γ=111.87(1)°;单胞体积为1870(1)A~3,z=2,Dc=1.960g·cm~(-3).晶体结构通过重原子法及差值Fourier合成解出,经多轮全矩阵最小二乘方修正,最终偏离因子R值为0.055.结果表明,晶体结构是由中性三核钼簇分子所组成.分子中三个Mo原子成等边三角形排布,Mo—Mo平均键长为2.725(3)A,相当于Mo—Mo单键的距离.在三角形面的一方,有一个μ_3~(—S)原子将这三个Mo原子桥联起来,形成单帽三核簇.另外,每两个Mo原子之间有一个S_2基因,起二重桥基的作用.每个Mo原子还由一个[S_2P(OEt)_2]~-基团的两个S原子配位,从而达到畸变五角双锥七配位。     

三核钼原子簇化合物的研究——Mo_3(μ_3—S)(μ—S)(μ—Cl)_2[S_2P(OEt)_2]_4Cl的晶体与分子结构

该簇合物系黑色片状晶体。空间群为P。对5103个I≥3σ(I)的独立衍射的最终R因子为0.062。结果表明,晶体由中性单硫帽三核钼原子簇化合物分子所组成。Mo—Mo间距分别为2.718(1),2.840(1)和2.796(1),表现一定程度的M—M成键作用。两个Cl原子和一个S原子作二重桥,使得以上这七个原子形成一个缺顶点的类立方烷构型。此外,每个钼原子还由其它三个原子配位以形成八面体配位构型。其中一个[S_2P(OEt)_2]~-基团通过两个硫原子分别与两个钼原子配位,起到一种新颖的二重桥的作用。     

三核钼原子簇化合物研究Mo3(μ3-O)(μ-S2)3[S2P(OEt)2]3Cl的合成、晶体与分子结构

本文研究的钼簇合物晶体呈橙黄色菱形片状, 属单斜晶系。晶胞参数: a=0.8253(5), b=2.1018(10), c=2.1531(17) nm, β=90.89(6)(°), V=3.734(7) nm, z=4, D_c=1.934 g·cm~3。晶体空问群为P2_1/n。晶体结构通过直接法和Fourier合成法解出, 偏离因子R=0.061。结果表明, 晶体系由兰核钼簇中性分子所组成, 分子中三重桥氧将呈等边三角形的三核钼联结起来, 每两个钼原子之间还有一个双硫基团作为二重桥, 其中一个S原子基本上与三核钼共面, 另一个处在平面外与三重桥氧相对的另一侧, 此外每个钼原子还由一个[S_2P(DEt)2]~-基团中的两个S原予补充端基配位, 使钼原予的局部配位接近于五角双锥。另外, 有一个氯原子将位于[Mo_3]平面外的三个S原子联结, S-Cl之间有微弱成键作用。     

三核钼原子簇化合物的研究——Mo_3(μ_3—O)(μ_2—S_2)_3[S_2P(OEt)_2]_3I的晶体与分子结构

本文所研究的晶体系金黄色菱片状。空间群为单斜晶系的P2_1/n。晶体结构主要用重原子法解出,经全矩阵最小二乘方精修,对4387个I≥2σ(I)的独立衍射的最终R因子值为0.047。结果表明,晶体结构由单氧帽中性三核钼簇合物分子所组成。Mo—Mo间距平均为2.626(4),Mo—O间距平均为2.036(2)。每两个钼原子之间还有一个S_2~(2-)基团作二重桥,其中一个S原子基本上处在三个钼原子构成的平面上,另一个处在平面外与μ_3-O原子相对的另一边。此外,每个钼原子还由一个[S_2P(OEt)_2]~-基团中的两个S原子补充配位,使得钼原子的局部配位氛接近于五角双锥。另外,在这三个平面外的S原子的顶部还有一个碘原子对这三个S原子起三重桥联作用,使得簇廓中的部份原子形成扭曲的类立方烷结构。     

三核钼原子簇化合物研究——(C_5H_7S_2)_3[Mo_3(μ_3—S)(μ_2—S_2)_3Cl_7]的晶体与分子结构

(C_5H_7S_2)_3[Mo_3(μ_3-S)(μ_2-S_2)_3Cl_7]晶体的空间群为Pnam;晶胞参数:a=17.226(4),b=14.306(7),c=15.074(4);z=4,ρ_(obs)=2.03克/厘米~(-3),ρ_(calc)=2.063克/厘米~(-3)。晶体结构由重原子法解出,并经全矩阵最小二乘方精修,偏离因子R值为0.068。研究结果显示出,晶体结构由三核钼簇阴离子[Mo_3(μ_3-S)×(μ_2-S_2 )_3Cl_7]~(3-)以及环绕着它的平面状的阳离子(C_5H_7S_2)~ 所组成。簇阴离子中,三个处在等边三角形顶点的Mo原子,由一个μ_3—S原子将其联系在一起,同时,每两个Mo原子之间还由一个S_2基团桥联,Mo—Mo间距分别为2.755(1),2.755(1),2.743(1)。此外,每个Mo原子还由两个Cl原子配位,使得Mo原子近邻的所有配位原子一起,形成接近五角双锥构型。簇阴离子中还有一个不与Mo原子直接配位的Cl原子,处在三个μ_2—S_2基团之间,而且与这三个S_2的一端S原子有一定程度的成键。簇阴离子整体接近c_(3v)对称性。用Cottonm~([1])等简化量化方法定性地分析了{Mo_3}体系的M—M成键情况,满意地解释了Mo—Mo间距和分子的磁性。     

三核钼原子簇化合物的研究——(Et_4N)_2[Mo_3(μ_3—O)(μ_3—Cl)(μ_2—Cl)_3Cl_6]·EtOH的晶体与分子结构

本文所研究的晶体属单斜晶系,空间群为P2_1/C。晶体结构由重原子法及差值Fourier合成解出,最小二乘方修正,对3261个I≥3σ(I)独立衍射的最终R因子为0.040。晶体结构由两套四乙基胺阳离子及三核钼原子簇阴离子组成。在簇阴离子中,三个钼原子呈等腰三角形分布。Mo—Mo间距为2.601(1),2.608(1)及2.642(1),表明金属原子间较强的成键作用。一个μ_3-O原子及一个μ_3-Cl原子分别处在三角形的上下与钼原子形成三角双锥簇核。每两个钼原子之间还各由一个与钼三角形共面的μ_2-Cl原子桥联。此外,每个钼原子还有两个端基Cl原子作为补充配位,从而使每个钼原子的配位成为稍为畸变的八面体。     

三核钼原子簇化合物研究——(Et_4N)_2[Mo_3(μ_3—O)(μ_2—Cl)_3(Oac)_2Cl_5]的晶体与分子结构

本文报道的化合物为黑色准八面体状晶体,属斜方晶系,空间群为Pna2_1,晶胞参数为:a=17.815(1),b=16.629(2),c=12.003(1)A,z=4,ρ_(obs)=1.80g·cm~(-3),ρ_(calc)=1.804g·cm~(-3),晶体结构用重原子法解出,经全矩阵最小二乘方精修,对2584个 I≥3σ(I)的独立衍射的最终偏离因子R为 0.048.结果表明,晶体结构由四乙基胺阳离子和三核钼簇阴离子所组成.簇阴离子是单(μ_3—0)帽三核簇,Mo—Mo间距平均为2.60(2)A.在与μ_3—O原子相对的Mo_3。三角形面的另一方,每两个Mo原子之间各由一个C1原子桥联.这七个原子形成一种缺顶点的畸变类立方烷构型.另外,每个Mo原子还由其他三个原子补充配位成接近八面体构型.这些配位原子是两个乙酰基的氧原子和5个氯原子.乙酰基的两个氧原子分别与相邻两个Mo原子配位.簇阴离子接近于C_m对称性。     

CRYSTAL STRUCTURE OF Mo_3(μ_3-O) (μ-S_2)_ 3 [S_2P(OEt)_2]_3I

<正> Mr=1178.9, monoclinic, P21/n, a=16.570(2), b=12.370(1), c=20.007(2) A,β=99.97(1)°, V=4039.0A3, Z=4, Dx=1.938 Mgm-3, λ(MoKα)=0.7107A, μ(MoKα)=23.96 F(000)=2296, room temperature. Final R value=0.047 for 4387 unique observed reflections. It consists of neutral mono-oxo-capped trinuclear molybdenum cluster molecules with an average Mo-Mo bond length of 2.626(4)A and an average Mo-0 bond length of 2.036(2)8.     

THE SYNTHESIS AND STRUCTURE OF THE CLUSTER COMPOUND {(Mo_3(μ_3-O)(S_2)_3[S_2P(OEt)a]3)2Cl}FeCl_4

<正> INTRODUCTION. Resently a series of M2-type trinuclear Mo clusters with the formula {Mo_3(μ-Y)(S_2)_3[S_2P(OEt)_2]_2]_3}X, (Y=O or S; X=Cl or I) have been synthesized by our research group through either the reduction of the higher valence Mo(V) compounds or the oxidation of the middle valence Mo(Ⅲ) species. In this paper we report a novel type of cluster cation     

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 OF Mo_3(μ3-S)_2(μ-Cl)_3[S_2P(OEt)_2]_3

<正> M=1013.98, hexagonal, P63/m, a=b=15.492(2), c=8.530(4)A, γ=120°, V=1773A3, Z=2, Dc=1.899°g.cm-3. Final R=0.042 for 611 reflections.This is a Bl(bicapped) type trinuclear molybdenum cluster with two S capping atoms located on the 63 axis and exhibits full D3h symmetry. The Mo-Mo distances are 2.606(1)A, with a bond order of 11/3. It is paramagnetic.     

CRYSTAL STRUCTURE OF Mo_3(μ3-S)(μ-S)_2[S_2P(OEt)_2]_3][SOP(OEt)_2](0)_2

<正> M=1140.85, monoclinic, P21/c. a=12.748(2), b=14.320(2), c=23.118 (3)A,β=101.07(1)°, V=4141(2)A3, Z=4, Dc=1.830 g.cm-3. Final R=0.039 for 4160 reflections.The title compound is a rather irregular trinuclear molybdenum cluster having only two M-M bonds with two shorter Mo-Mo distances of 2.808(1), 2.839(1), and one longer Mo-Mo distance of 3.337(1)8. The existence of two Mo-Mo bonds is coincident with the electron counting for {Mo3} cluster core, and may be regarded as a result of the oxidation of a compound Mo3(μ3-S)(μ-S)2 (μ-L)[S2P(OEt)2]4(L') (L'=neutral ligands)1 characterized by us previously.     

三核钼原子簇化合物的研究——两个三核钼原子簇(C_5H_7S_2)[Mo_3(μ_3—O)(μ—X)_3(μ—OAc)_3Cl_3](X=Cl,Br)的晶体和分子结构

本文采用单晶X射线衍射分析研究了两个属于异质同晶的三核钼簇合物的晶体和分子结构。两种晶体的空间群均为P2_1/C;Z=4。两个晶体结构分别采用重原子法和直接法解出,最小二乘方精修,偏离因子R分别为0.061和0.051。研究表明,它们都属于由一个三核钼簇阴离子和一个平面状的(G_5H_7S_2)~ 阳离子构成的离子型晶体。阴离子中,排布成等边三角形的三核钼由一个μ_3—O桥连接,每两个钼原子之间又具有一个μ—X(X=Cl,Br)桥和一个μ—OAc桥,此外,每个Mo原子又再和一个氯原子相连,使得每个Mo原子周围组成扭曲八面体的局部配位。本文还比较了两个化合物的结构关系,并对化合物Ⅱ中μ—Br取代了化合物Ⅰ中的相应μ—Cl,而造成两个化合物中Mo—Mo,Mo—(μ_3—O),Mo—Cl(端基)诸键键长的区别加以讨论,与此同时,还讨论了乙酰氧基对稳定簇骼所起的作用。     

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。     

CRYSTAL STRUCTURE OF {Mo_3(μ_3-S)(μ-S)_3 [S_2P(OEt}_2]_4·PhCH_2CN}

<正> Mr=2548.12, Triclinic, P1, a=15.941(5), b=15.957(2),c=20.240(6)A, α=76.41(2),β=83.87(2),γ=74.41(2)°,V=4814.6A3, Z=4, Dc=1.757g.cm-3, Final R=0.053 for 11867 reflections. There are two crystallographically independent M1 type trinuclear Mo cluster molecules with 'loose coordination site', A and B, in an asymmetric unit of the title crystal. They are formulated as {Mo3S4(u-dtp)(dtp)3.PhCH2CN}(dtp=[S2P(OEt)2]-) and have essentially identical cluster molecular configuration, but differ from each other in the conformations for the phenyl rings of the ligands PhCH2CN. The lengths of the Mo-Mo bonds are 2.750(1), 2.753(1),and 2.768(1)A for molecule A and 2.742(1), 2.756(1), and 2.764(1)A for molecule B, while the dihedral angles betweem the phenyl ring and the {Mo3} triangle are 25.0° and 94.9° for A and B respectively.     

RESEARCH ON TRINUCLEAR MOLYBDENUM CLUSTER COMPOUNDS——CRYSTAL AND MOLECULAR STRUCTURE OF Mo_3(μ_3-S)(μ_2-S_2)_3[S_2P(OEt)_2]_3Cl

The title crystal is straw-yellow in colour, belonging to the triclinic system. The space group is P with the following unit cell parameters:a=11.570(2), b=13.093(1), c=14.399(2), α=102.62(1), β=102.15(1), γ=111.87 (1)°, V=1870(1), Z=2, D_(calc)=1.960g·cm~(-3).The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares to a final conventional R factor of 0.055. The results show that the crystal structure consists of neutral trinuclear Mo cluster molecules, in which three independent Mo atoms form an equilateral triangle with an average side length of 2.725(3), corresponding to a Me-Me single bond. On one side of the triangle one μ_3-S atom binds the three Mo atoms together to form a monoeapped trinuclear cluster. In addition, three S_2 radicals acting as μ_2 bridges are located between each two Mo atoms. Each Mo atom is also coordinated to two terminal S atoms of an [S_2P(OEt)_2]~- radical so as to complete a distorted pentagonal bipyramid configuration.     

(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。     

STUDY OF REDOX PROPERTIES OF TETRANUCLEAR DENUM CLUSTER COMPOUND {Mo_4(μ_3-S)(μ_3-O)[S_2P(OEt)_2]_6}

<正> The redox properties of tetranuclear molybdenum cluster {Mo4(μ3-S)3(μ3-O)CS2P(OEt)2D6}(1)have been investigated by linear sweep voltammetry,cyclic voltammetry,differential pulse voltammetry and controlled potential coulome-try.It is showed that the compound undergoes two consecutive near reversible one-electron reductions at-0.03V and-0.79V respectively and a near reverisble one-electron oxidation at 0.98V with scan rates from 25 mV/sec to 1V/sec in cyclic voltammetric measurements.Three stable peaks can still be seen after several hours of repeated slow speed scan(1mV/sec)in differential pulse voltammetry.These evidences suggest the high structural stability of this cluster compound.     

CRYSTAL STRUCTURE OF [Mo_3S_4 (μ-CH_3COO) [S_2P(OEt)_2]_3 (py)] (CH_3COOCH_2CH_3)

<正> [Mo3S4(μ-CH3COO)[S2P(OEt)2]3(py)]·(CH3COOCH2CH3) , Mr = 1197. 96,monoclinic,P21/n,a=13. 158(2),b=23. 153(5), c=16. 175(3) A,β = 112. 79(1)°,V=4543. 1(7)A3,Z=4, Dc= 1. 751g/cm-3,λ(MoKa) = 0. 71073A ,μ= 13. 799cm-1,F(000) = 2408. Final R=0. 067 for 4000 reflections. The structure consists of the neutral cluster molecule [Mo3S4(μ-OAc) (dtp)3(py)] (dtp = [S2P(OEt)2]) and the solvent ethyl acetate (AcOEt). The three Mo-Mo bond lengths in the title compound are 2. 691(2) ,2. 747(2) ,2. 762(2) A ,whereas the Mo-N bond length in Mo(3) position is 2. 36(2)A. The important bond lengths of these Mo clusters with (py) ring at the loose coordination site are listed for comparison.