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用能量一致相对论有效核芯势和参阅文献基础上添加极化函数4f2g的价基组,在密度泛函理论(DFT)、多体微扰MPn和组态相关理论QCISD水平上计算了LaCl分子结构、离解能和振动频率.根据原子分子反应静力学原理,导出LaCl分子基态可能的电子状态和离解极限,用DFT中的B3LYP方法计算了基态X1Σ+势能曲线,拟合得到了MurrellSorbie解析势能函数及其在平衡位置附近的Dunham展开式,由此计算的振转常数与实验光谱数据完全符合.得到的解析势能函数可用于计算振转光谱精细跃迁结构和原子分子碰撞反应动力学过程
关键词:
LaCl
相对论有效核芯势
解析势能函数
振转光谱常数 相似文献
83.
84.
二茂基环己氧基稀土化合物的合成、分子结构和催化活性 总被引:1,自引:0,他引:1
通过Cp_3Ln(Ln=Sm, Yb)和环己醇在THF溶剂中按1:1摩匀比反应,合成了标题 化合物[Cp_2LnOC_6H_(11)]_2(Ln=Sm, Yb)。化合物经元素分析、红外光谱分析表 征。镱配合物经X单晶衍射分析。它是一个以氧原子为桥的二聚体,环己烷基呈椅 式构型,O-C(环己烷基)键处于平伏e键位置。在上述基础上,尝试了它对己内 酯的催化聚合反应,发现标题化合物对己内酯聚合具有一定的催化活性。进一步合 成了[Cp_2YbOC_6H_(11)]与己内酯的1:4预聚反应产物,发现预聚物催化己内酯聚 合活性比标题化合物大大增强,从而说明催化聚合过程中引发反应速率慢是影响标 题化合物表观催化活性的重要因素。 相似文献
85.
Two new copper complexes, [Cu(cbdc)(phen)(H2O)]·2H2O (1) and [Cu2(cbdc)(phen)2(H2O)2](ClO4)2·H2O (2) (cbdc= 1,1-cyclobutanedicarboxylate and phen= 1,10-phenanthroline), were synthesized by reaction of cbdc with Cu(ClO4)2 and phen in ethanol aqueous solution. Complex 1 crystallizes in monoclinic system with space group P2(1)/c and a=0.9428(4) nm, b= 1.2183(5) nm, c= 1.6265(7) nm, β= 102.418(5)°, V= 1.8246(13) nm^3, Z=4, R=0.0445, wR2=0.0947. The structure of 1 is discretely mononuclear, which is packed by π…π interaction forming a 3D supramolecular structure where Cu(Ⅱ) ion is five-coordinated and has square-pyramidal coordination geometry. Its thermal decomposition procedure detail was studied by thermal analysis TG-DSC. Complex 2 belongs to monoclinic system with space group P2(1)/c and a=0.8897(3) nm, b= 1.9130(8) nm, c= 1.9936(8) nm,β=99.04(2)°, V=3.351(2) nm^3, Z=4, R=0.0540, wR2=0.1102. The structure of 2 is a discrete binucleus, where Cu(1) is four-coordinated by phen and cbdc in a square-planar geometry while Cu(2) is five-coordinated by phen, one O of cbdc and two H2O, which can be best described as distorted trigonal-bipyramidal geometry. Cu(1) and Cu(2) are linked by carboxylic group of cbdc in a bidentate bridging fashion. Variable-temperatttre magnetic susceptibilities of 2 in 2-300 K showed that its magnetic behavior obeyed Curie law. 相似文献
86.
Wang JQ Cai S Jin GX Weng LH Herberhold M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(24):7342-7350
The 16-electron half-sandwich complex [Cp*Ir[S2C2(B10H10)]] (Cp* = eta5-C5Me5) (1a) reacts with [[Rh(cod)(mu-Cl)]2] (cod = cycloocta-1,5-diene, C8H12) in different molar ratios to give three products, [[Cp*Ir[S2C2(B10H9)]]Rh(cod)] (2), trans-[[Cp*Ir[S2C2(B10H9)]]Rh[[S2C2(B10H10)]IrCp*]] (3), and [Rh2(cod)2[(mu-SH)(mu-SC)(CH)(B10H10)]] (4). Complex 3 contains an Ir2Rh backbone with two different Ir-Rh bonds (3.003(3) and 2.685(3) angstroms). The dinuclear complex 2 reacts with the mononuclear 16-electron complex 1a to give 3 in refluxing toluene. Reaction of 1a with [W(CO)3(py)3] (py = C5H5N) in the presence of BF3.EtO2 leads to the trinuclear cluster [[Cp*Ir[S2C2(B10H10)]]2W(CO)2] (5) together with [[Cp*Ir(CO)[S2C2(B10H10)]]W(CO)5] (6), and [Cp*Ir(CO)[S2C2(B10H10)]] (7). Analogous reactions of [Cp*Rh[S2C2(B10H10)]] (1 b) with [[Rh(cod)(mu-Cl)]2] were investigated and two complexes cis-[[Cp*Rh[S2C2(B10H10)]]2Rh] (8) and trans-[[Cp*Rh[S2C2(B10H10)]]2Rh] (9) were obtained. In refluxing THF solution, the cisoid 8 is converted in more than 95 % yield to the transoid 9. All new complexes 2-9 were characterized by NMR spectroscopy (1H, 11B NMR) and X-ray diffraction structural analyses are reported for complexes 2-5, 8, and 9. 相似文献
87.
开放式有机-无机杂化骨架配位聚合物[Sn(SO4)(BDC)(H2O)]的合成和晶体结构 总被引:2,自引:0,他引:2
具有大孔径、高比面积的金属有机骨架结构已成为微孔材料研究领域的一个热点,但是其合成设计目前还主要集中在过渡金属元素和镧系元素为接点的微孔材料上.尽管硅、铝族元素已被广泛地用于构建和合成微孔材料,但由于其电荷高、极性强,故在开放有机金属骨架微孔材料的设计与合成中很少被应用.文献中巧妙地以锌离子为接点,成功地将硅氧簇引入配位聚合物的骨架中. 相似文献
88.
An environmentally benign and efficient process for the preparation of 3-(substituted methylthio)-4-phenyl-5- (3,4,5-trimethoxyphenyl)-4H-1,2,4-triazole was achieved by the reaction of 4-phenyl-5-(3,4,5-trimethoxyphenyl)- 4H- 1,2,4-triazole-3-thiol with different halides in aqueous media mediated by indium trichloride in high yields. 相似文献
89.
Tian YQ Zhao YM Chen ZX Zhang GN Weng LH Zhao DY 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(15):4146-4154
Attempts to create metal-organic frameworks (MOFs) with zeolitic topologies, metal (zinc(II) and cobalt(II)) imidazolates have repeatedly been used as the metal-organic motifs of inorganic silicate analogues. By modulating the synthetic strategy based on the solvothermal and liquid diffusion method, seven further MOFs (including at least three zeolitic MOFs) of zinc(II) imidazolates, [Zn(im)2.x G] (G=guest molecule, x=0.2-1) 1 a-7 a, have been successfully synthesized. Of these, 1 a-3 a are isostructural with the previously reported cobalt analogues 1 b-3 b, respectively, while 4 a-7 a are new members of the metal imidazolate MOF family. Complex 4 a exhibits a structure related to silicate CaAl2Si2O8 of CrB4 topology, but with a higher network symmetry; complex 5 a has a structure with zeolitic DFT topology that was discovered in zeolite-related materials of DAF-2, UCSB-3, and UCSB-3GaGe; complex 6 a demonstrates an unprecedented zeolite-like topology with one dimensional channels with 10-rings; and 7 a displays a structure of natural zeolite GIS (gismondine) topology. All of these polymorphous MOFs were created only by using certain solvents as structure-directing agents (SDAs). Further extensive metal-organic frameworks with zeolitic topologies can be envisaged if other solvents were to be used. 相似文献
90.
The synthesis of half-sandwich transition metal complexes containing both 1,2-dichalcogenolato-1,2-dicarba-closo-docecaborane (Cab(E,E)) [Cab(E,E)=E(2)C(2)(B(10)H(10)); E = S, Se] and N-heterocyclic carbene (NHC) ligands is described. Addition of mono-NHC ligand to the 16e half-sandwich dichalcogenolato carborane complexes [Cp*Rh(Cab(E,E))], [Cp*Ir(Cab(S,S))], [(p-cymene)Ru(Cab(S,S))] (Cp* = pentamethylcyclopentadienyl) gives corresponding mononuclear 18e dithiolate complexes of the type [LM(Cab(E,E))(NHC)]: [Cp*M(Cab(S,S))(1-ethenyl-3-methylimidazolin-2-ylidene)] (M = Ir (2), Rh (3)), [Cp*Rh(Cab(E,E))(3-methyl-1-picolyimidazolin-2-ylidene)] [E = S (6), Se (7)], [(p-cymene)Ru(Cab(S,S))(NHC)] [NHC = 1-ethenyl-3-methylimidazolin-2-ylidene (4), 3-methyl-1-picolyimidazolin-2-ylidene (8)], whereas bis-NHC give centrosymmetric binuclear complexes [{Cp*M(Cab(S,S))}(2)(1,1'-dimethyl-3,3'-methylene(imidazolin-2-ylidene))] [M = Rh (10), Ir (11)]. The complexes were characterized by IR, NMR spectroscopy and elemental analysis. In addition, X-ray structure analyses were performed on complexes 2-4, 6, 8, 10 and 11. 相似文献