ANALYSIS OF ANGULAR OVERLAP PARAMETERS FOR THE LAOXEU3+ (X = CL, BR, I) SERIES

The Angular Overlap Model (AOM) is applied to the LaOX:Eu3+(X = Cl, Br, I) series involving sigma, pi, delta and phi effects based on the experimental energy levels. The calculations are made in two cases. (1) Consider oxygen and halogen having the same bond-length. (2) Consider the real structure. In both cases, the results show that for sigma-bonding parameters, the values of e(sigma) decrease with increasing charge number of halogen, i.e. Cl- > Br- > I-, this indicates that the bonding ability also decreases with this order. The absolute values of each parameter are much larger than zero-therefore they all must be included in a practical analysis. In the second case, the values of the e(pi) parameter are negative, which means a ''back-bonding'' is formed, and this is profitable for the formation of sigma-bonding, usually referred to as ''synergic effect''.

STUDIES ON THE REACTIONS OF TRANSITION-METAL HYDRIDES WITH HETEROCUMULENES .6. REACTION OF CP2ZR(H)CL WITH RNCS (R=C6H5, 2-C10H7, C-C6H11 AND N-C4H9)

The novel NS-containing zirconacycle complexes Cp2ZrCl[SC(H)NR] (1a, R = C6H5; 1b, R = 2-C10H7; 1c, R= C-C6H11; 1d; R = n-C4H9) were obtained by insertion reactions of Cp2Zr(H)Cl with RNCS. 1(a-d) could react further with Cp2Zr(H)Cl to yield a sulphur-bridging compleX (Cp2ZrCl)2S (2) and a Schiff base RN=CH2. The crystal structure of la has been determined by X-ray analysis.

KX(X=Cl,Br,I)晶体中Eu~(2+)离子的4f~65d态能级计算

按着4f~6(~7F_J)和5dΓ_1耦合模型,提出了计算KX(X=Cl,Br,I)晶体中Eu~(2+)离子4f~65d能级的方法,导出了能级的参数表达式,并进行了数值计算,计算结果和实验符合较好.

SYNTHESIS AND CRYSTAL-STRUCTURE OF ([(C5H9C5H4)ER(THF)]2(MU-2-CL)3(MU-3-CL)2NA(THF)2).THF

The reaction of ErCl3 with one equivalent of C5H9C5H4Na generates the complex {[(C5H9C5H4)Er(THF)]2(mu2-Cl)3(mu3-Cl)2Na(THF)2}.THF, which crystallizes from hexane/THF. The X-ray crystal structure determination shows that each erbium is surrounded by one C5H9C5H4 ligand, two mu3-Cl, two mu2-Cl and one THF in a distorted octahedral arrangement.

SYNTHESES OF METHYLCYCLOPENTADIENYL DERIVATIVES OF LANTHANIDES (LN = LA-ND) AND CRYSTAL-STRUCTURES OF [(THF)2LI(MU-CL)2]2[MECPND(THF)] AND [LI(DME)3][MECPLA(NPH2)3]

The reaction of LnCl3.2LiCl with 1 equiv of MeCpNa in THF gives the complexes [(THF)2Li(mu-Cl)2]2[MeCpLn(THF)] (Ln = Nd (1), La (2)) in good yield. These precursors react further with 2 equiv of LiNPh2 to produce the new complexes [Li(DME)3][MeCpLn(NPh2)3] (Ln = La (3), Pr (4), Nd (5)). They have been characterized by elemental analyses and IR and NMR spectra, as well as by structural analyses of 1 and 3. The chloride 1 crystallizes in the monoclinic space group P2(1)/n (No. 14) with a = 12.130 (5) angstrom, b = 17.343 (5) angstrom, c = 17.016 (5) angstrom, beta = 108.54 (3)-degrees, V = 3393.87 angstrom3, Z = 4, and D(c) = 1.45 g/cm3. Least-squares refinement led to a final R value of 0.051 (I greater-than-or-equal-to 3-sigma(I(o))) for 2004 independent reflections. Complex 3 crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 18.335 (6) angstrom, b = 16.576 (5) angstrom, c = 17.461 (6) angstrom, beta = 96.04 (3)-degrees, V = 5277.17 angstrom3, D(c) = 1.26 g/cm3, Z = 4, and R = 0.057 (I greater-than-or-equal-to 2.5-sigma(I(o))) for 3378 reflections. The structure of 3 consists of discrete ion pairs [Li(DME)3]+ and [MeCpLa(NPh2)3]- with average La-N and La-C(ring) distances of 2.459 (8) and 2.84 (1) angstrom, respectively.

[(O)MoCu_3(μ_3-S)_3(μ_3-Cl)(PPh_3)_3]·2THF的合成及其晶体结构

固体化合物(NH_4)_6Mo_7O_(24)·4H_2O和(PPh_3)_2CuCl与饱和液体NH_4HS反应获得桔红针状标题晶体。晶体空间群为P2_1/c,晶胞参数a=11.742(2),b=28.186(7),c=19.304(3),β=100.57(2)°,V=6280.4(?)~3,D_c=1.46g/cm~3,Z=4,F(000)=2816。在3≤2θ≤45°范围内收集到8414个独立衍射强度数据,其中3856个I≥1.5σ(I)强度数据参加结构计算。标题化合物分子是以{MoCu_3S_3Cl}类立方烷型簇为核心的分子,Mo—Cu的平均距离为2.716。

(LaCl)(THF)_2(μ-Cl)_4[Li(THF)_2]_2配合物的合成及晶体结构

LaCl_3和LiCl在THF中于室温反应,以已烷为沉淀剂,在-78℃得到晶体,经色谱、元素分析及X射线晶体结构测定,得到了组成为(LaCl)(THF)_2(μ-Cl)_4[Li(THF)_2]_2的配合物.在约-80℃收集该配合物晶体的衍射强度数据,计算结果表明属于单斜晶系,P2_1/c空间群,其晶胞常数a=10.542(4)(?),b=32.236(14)(?),c=11.182(6)(?);β=113.50(3)°,最后R值为0.0477.四个氯桥键构成了分子的基本骨架,表明桥键在小配体轻希土双金属配合物结构中具有稳定作用.

Eu~(3+):LaOX(X=Cl,Br,I)晶体的角重迭晶场参数计算

本文运用角重迭模型(AOM)在考虑其全部四个参数e_σ、e_π、e_δ及e_φ的基础上首次对Eu~(3+):LaOX(X=Cl,Br,I)晶体在晶场作用下的能级劈裂进行了拟合.

LaX_3(X=F、Cl、Br、OH)晶体中的化学键参数计算

稀土化合物中稀土离子和配位体的成键性质一直是人们注意研究的课题之一,一般认为属于离子键,但具有少量的共价性,然而,具体的数量级尚不清楚。本文利用Phillips,VanVechten和Levine理论,对LaX_3(X=F、Cl、Br、OH)晶体的键性和有关参数进行了具体计算,定量指出了镧离子和配体成键的离子性和共价性程度,比较了各晶体中有关的键参数,发现了和宏观物理现象相关的规律。1 理论公式

SYNTHESIS AND X-RAY CRYSTAL-STRUCTURE OF A MONOPENTAMETHYLCYCLOPENTADIENYL DERIVATIVE OF GADOLINIUM (NA(MU-2-THF)[(C5ME5)GD(THF)]2(MU-2-CL)3(MU-3-CL)2)2.6THF

The reaction of GdCl3 with 1 equiv of NaC5Me5 generates a neutral complex C5Me5GdCl2(THF)3 and a novel complex {Na(mu-2-THF)[(C5Me5)Gd(THF)]2(mu-2-Cl)3(mu-3-Cl)2}2.6THF whixh recrystallizes from THF in triclinic, the space group P1BAR with unit cell dimentions of a 12.183(4), b 13.638(6), c 17.883(7) angstrom, alpha-110.38(3), beta-94.04(3), gamma-99.44(3)-degrees, V 2721.20 angstrom-3 and D(calc) 1.43 g cm-3 for Z = 1. Least-squares refinement of 2170 observed reflections led to a final R value of 0.047. The title complex consists of two Na(mu-2-THF)[(C5Me5)Gd(THF)]2(mu-3-Cl)3(mu-3-Cl)2 units bridged together via two mu-2-THF to Na coordination. Each Gd ion is surrounded by one C5Me5 ligand, two mu-3-Cl, two mu-2-Cl and one THF in a distorted octahedral arrangement with average Gd-C(ring) 2.686(33), Gd-mu-2-Cl 2.724(7), Gd-mu-3-Cl 2.832(8) and Gd-O 2.407(11) angstrom. The sodium ion coordinates to two bridging THF, two mu-2-Cl and two mu-3-Cl to form a distorted octahedron with average Na-mu-2-O, Na-mu-2-Cl and Na-mu-3-Cl of 2.411(21), 2.807(15) and 2.845(12) angstrom, respectively.

配合物[Li(THF)_2]_2(μ—Cl)_4[(η~5—CH_3C_5H_4)Nd·THF]的合成及其晶体结构

环戊二烯基希土氯化物是一类合成希土有机配合物的重要前身。尽管在1980年前没能成功地合成含轻希土元素的这类配合物,但目前已发现,采用具有较大体积的取代环戊二烯做配体,如C_5Me_5H,C_5H_3〔Si(CH_3)_3〕_2H,C_5Me_4C_3H_7H和桥联的配体(C_5H_4)_2(CH_2)_3H_2都可得到相应的取代环戊二烯基轻希土氯化物。控制LnCl_3和CpNa的反应摩尔比也可以成功地得到这类轻希土的环戊二烯基氯化物。

STUDY OF BIMETALLIC COMPLEXES OF RARE-EARTH LITHIUM - SYNTHESIS AND CRYSTAL-STRUCTURE OF THE (LACL)DME(MU-2-CL)5(MU-3-CL) (LA.DME)LI(THF)2

The reaction between LaCl_3 and LiCl in THF at room temperature, with hexane as precipitant and glycol dimethyl ether as complexing agent, has been studied. A complex with the composition of (LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2 has been synthesized, its structure was studied by single crystal X-ray diffraction technique. The diffraction intensities were collected at about —100℃. The complex belongs to the triclinic space group P1 with α=11.123(3), 6=16.564(5), c=8.653(3)A, α=95.16(3), β=...

稀土-锂双金属配合物的研究——(LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2的合成及其晶体结构

在稀土有机化学中,[Cp_2LnCl]_2和[Cp_2LnCl_2LiL_2][Cp为取代或未取代的环戊二烯基,Ln为稀土离子(III),L为Lewis碱]型化合物是重要的中间物。对含锂烷基、芳基或烯丙基稀土化合物的研究也有着重要的意义。这类分子中含有型桥键结构。由于这类化合物难于结晶及其不稳定性,故很难进行系统的研究。 Rossmanith首先发现了NdCl_3-LiCl-THF溶液的存在。李毅用这一溶液很方便地合成了几个轻稀土-锂双金属有机化合物。但是,在稀土配位化学中,对氯化稀土-氯化锂配合物的研究还很少,对LnCl_3LiCl-THF溶液的认识也有待深化。本文合成了组成为(LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2的新型桥式链状配合物,并测定了晶体结构。这种类型的稀土双金属配合物尚未见报道。