M3NS3, die ersten Nitridsulfide der Lanthanide (M = La?Nd,Sm)

M₃NS₃, the First Nitride Sulfides of the Lanthanides (M = La? Nd, Sm) . The oxidation of the “light” lanthanides (M = La? Nd, Sm) with equimolar amounts of sulfur in the presence of NaN₃ as nitrogen source results in the formation of the first lanthanide nitride sulfides: M₃NS₃ (evacuated silica vessels, some NaCl as flux, 850°C, 7 d). NaCl is afterwards removed from the not moisture sensitive crude product (faint- or orange-yellow to amber-co- loured transparent needles, oftenly intergrown to feltlike bunches) upon rinsing with water. The crystal structure was determined from X-ray single crystal data for the example of Sm₃NS₃ (orthorhombic, Pnma (no. 62), a = 1 201.18(7), b = 394.32(3), c = 1 285.27(6) pm, Z = 4, R = 0.027, R_w = 0.024), and M₃NS₃ (M = La? Nd) proved to be isostructural from Guinier powder data. There are three crystallographically different M³⁺ cations in six- (1 X) and sevenfold (2 X) coordination of the N^3? and S^2? anions. [(N^3?)(M³⁺)₄] tetrahedra connected via two corners forming linear chains [N(M1)_1/1(M2)_1/1(M3)_2/2] ⁶⁺ build up the main structural feature. Arranged in the manner of a closest packing of rods, they are held together by three crystallographically different S^2? which take care for charge neutrality and three-dimensional interconnection.     

Formation of M(4)Se(4) cuboids (M = As, Sb, Bi) via secondary pnictogen-chalcogen interactions in the co-crystals MX(3)·Se[double bond, length as m-dash]P(p-FC(6)H(4))(3) (M = As, X = Br; M = Sb, X = Cl; M = Bi, X = Cl, Br)

The reactions of the group 15 trihalides, MX(3) (M = As, Sb, Bi; X = Cl, Br), with the phosphine selenide SeP(p-FC(6)H(4))(3) result in the formation of co-crystals of formula MX(3)·SeP(p-FC(6)H(4))(3). No reaction was observed with MI(3) (M = As, Sb, Bi). The structures of MX(3)·SeP(p-FC(6)H(4))(3) (M = As, X = Br 2; M = Sb, X = Cl 3; M = Bi, X = Cl 5; M = Bi, X = Br 6) have been established, and are isomorphous, crystallising in the cubic I23 space group. All the structures feature a primary MX(3) unit, which has three weak secondary MSe interactions to SeP(p-FC(6)H(4))(3) molecules. However, each of these SeP(p-FC(6)H(4))(3) molecules bridges three MX(3) molecules, resulting in the generation of an M(4)Se(4) (M = As, Sb, Bi) distorted cuboid linked by the pnictogen-chalcogen interactions. Four opposing corners of the cuboid are occupied by the M atom (M = As, Sb, Bi) of an MX(3) pyramid, and the other four by the selenium atom of the phosphine selenide.     

噻吩在M(111)(M=Pd,Pt,Au)表面的吸附(英文)

采用密度泛函理论(DFT),选取DMol3程序模块,对噻吩在M(111)(M=Pd,Pt,Au)表面上的吸附行为进行了探讨.通过对噻吩在不同底物金属上的吸附能、吸附构型、Mulliken电荷布居、差分电荷密度以及态密度的分析发现,噻吩在Pd(111)面上的吸附能最大,Pt(111)面次之,Au(111)面最小.吸附后,噻吩在Au(111)面上的构型几乎保持不变,最终通过S端倾斜吸附于top位;噻吩在Pd(111)及Pt(111)面上发生了折叠与变形,环中氢原子向上翘起,最终通过环平面平行吸附于hollow位.此外,噻吩环吸附后芳香性遭到了破坏,环中碳原子发生sp3杂化,同时电子逐渐由噻吩向M(111)面发生转移,M(111)面上的部分电子也反馈给了噻吩环中的空轨道,这种协同作用最终导致了噻吩分子稳定吸附于M(111)面.     

M2TNR(M=AG, CHZ)的制备和晶体结构

通过三硝基间苯二酚(TNR,斯蒂酚酸)和氨基胍(AG)重碳酸盐、碳酰肼(CHZ)反应,制备斯蒂酚酸氨基胍和斯蒂酚酸碳酰肼。并用X-射线衍射分析、元素分析、差示扫描量热法和红外光谱对其进行了结构表征。它们的分子式分别为(NH2NHCNHNHNH2)2^+[C6H(NO3)3O2]^2.0.5H2O,(NH2NHCONHNH3)2^+[C6H(NO3)3O2]^2^-,二者都属于单斜晶系,C2/c空间群。     

[M(dap)3]2(Sb2Se5)·xH2O(M=Ni,x=2;M=Zn,x=0)的溶剂热合成及晶体结构

利用溶剂热法合成了2种新的有机杂化锑硒化合物[Ni(dap)3]2(Sb2Se5)].2H2O(1)和[Zn(dap)3]2(Sb2Se5)](2)(dap=1,2-丙二胺),单晶X射线衍射分析结果表明,1属于三方晶系,P3121空间群,晶胞参数为a=10.7574(14),b=10.7574(14),c=31.672(4),γ=120.00°,z=4。2属于单斜晶系,P21空间群,晶胞参数为a=10.772(2),b=16.391(3),c=11.704(2),β=100.912(4)°,z=4。在2种化合物中,Ni2 与Zn2 离子分别与3个dap配体螯合形成畸变八面体几何构型,其中dap配体的N原子是无序的,而二聚[Sb2Se5]2-阴离子是由2个SbSe3三角锥共用1个Se原子连接而成。     

Ylenes in the M(II)→Si(IV) (M=Si, Ge, Sn) coordination mode

The reaction of the methimazolyl (mt, i.e., 2-mercapto-1-methylimidazolide) substituted silane Si(mt)(4) with SnCl(2) and GeCl(2) in dioxane affords the paddlewheel-shaped complexes [ClSi(μ-mt)(4)MCl] (M=Sn (1) and Ge (2), respectively). These compounds represent the first crystallographically characterized hexacoordinate silicon complexes comprising a Sn or Ge atom in the Si coordination sphere. An attempt to synthesize the related silicon compound 3 [ClSi(μ-mt)(4)SiCl] instead afforded the trisilane [ClSi(μ-mt)(4)Si-SiCl(3)] (3a), which provides the first crystallographic evidence for the feasibility of oligosilanes with adjacent hexacoordinate Si atoms. One of the hexacoordinate Si atoms of 3a features the unprecedented (Si(2)S(4))Si skeleton. Natural bonding orbital (NBO) analyses of compounds 1, 2, 3a (and the target compound 3) revealed characteristics of M(II)→Si(IV) (for 2 and 3) or M(I)→Si(IV) (for 3a) dative bonding in the systems with M=Si and Ge, whereas compound 1 exhibits a covalent Sn(III)-Si(III) bond.     

Interactions of M(z)-X complexes (M = Cu, Ag, and Au; X = He, Ne, and Ar; and z = ±1)

The coupled cluster singles and doubles method with perturbative treatment of triple excitations is applied to calculate the potentials of M(z)-X complexes (M = Cu, Ag, and Au; X = He, Ne, and Ar; and z = ±1). The bond functions and the basis set superposition errors are considered to obtain accurate interaction energies. The potential energy curves of all complexes are obtained. The vibrational energy levels and the spectroscopic parameters for these complexes are determined. The analytical potential energy functions are also fitted based on the potential energies.     

M(bpy)2+3(M=Fe,Ru,Os)电子结构与相关性质

报导了对配合物Ｍ（ｂｐｙ）＾２＋３（Ｍ＝Ｆｅ,Ｒｕ,Ｏｓ）的量子化学密度泛函法研究的结果。Ｂ３ＬＹＰ／ＬａｎＬ２ＤＺ方法与基组的水平上进行计算,探讨Ｍ（ｂｐｙ）＾２＋３电子结构特征及相关性质,特别是中心原子对配合物的配位键长、光谱性质,电荷布局及化学稳定性等的影响规律,为该类配合物的合成,为分析光、电、催化作用机理提供理论参考。     

M(bpy)2+3(M=Fe,Ru,Os)电子结构与相关性质

报导了对配合物(M=Fe,Ru,Os)的量子化学密度泛函(DFT)法研究的结果.在B3LYP/LanL2DZ方法与基组的水平上进行计算,探讨的电子结构特征及相关性质,特别是中心原子对配合物的配位键长、光谱性质、电荷布居及化学稳定性等的影响规律,为该类配合物的合成,为分析光、电、催化作用机理提供理论参考.     

噻吩在M(111)(M=Pd,Pt, Au)表面的吸附

采用密度泛函理论(DFT), 选取DMol³程序模块, 对噻吩在M(111) (M=Pd, Pt, Au)表面上的吸附行为进行了探讨. 通过对噻吩在不同底物金属上的吸附能、吸附构型、Mulliken 电荷布居、差分电荷密度以及态密度的分析发现, 噻吩在Pd(111)面上的吸附能最大, Pt(111)面次之, Au(111)面最小. 吸附后, 噻吩在Au(111)面上的构型几乎保持不变, 最终通过S端倾斜吸附于top 位; 噻吩在Pd(111)及Pt(111)面上发生了折叠与变形, 环中氢原子向上翘起, 最终通过环平面平行吸附于hollow 位. 此外, 噻吩环吸附后芳香性遭到了破坏, 环中碳原子发生sp³杂化, 同时电子逐渐由噻吩向M(111)面发生转移, M(111)面上的部分电子也反馈给了噻吩环中的空轨道, 这种协同作用最终导致了噻吩分子稳定吸附于M(111)面.     

羰基原子簇化合物M3(CO)12(M=Fe,Ru,Os)的激光解离研究

在自制的仪器上以冲激光溅射铁、钌、锇的三核羰基原子簇化合物。由原位质谱观察和分析溅射产生的正负离子。比较了解离碎片及分布发现羰基锇原子簇化合物具有特殊的结构稳定性。它们不仅具有很强的金属键,而且锇与羰基分子还形成了很强的配位键。     

MAlH4(M=Li,Na)储氢材料*

氢能是一种新型的清洁能源,有望替代碳经济,而氢的储存是氢能应用的关键。近年来,研究集中在具有储氢容量高和可逆性好等优点的固态储氢材料上。许多新型储氢材料不断出现,其中以MAlH₄(M=Li, Na)为代表的金属复合氢化物体系被认为是最有前景的储氢材料之一。本文综述了MAlH₄(M=Li, Na)作为可逆储氢材料的研究现状,主要从吸放氢反应、储氢性能、反应机理、理论计算和存在的问题等方面进行了讨论,并指出其相关发展趋势。     

氧心羧桥异三核过渡金属簇合物[Fe2MO(CH3COO)6Py3].Py(1,M=Mn;2,M=Co;3,M=Ni)和[Fe2MO(CCl3COO)6(THF)3](4,M=Mn;5,M=Co;6,M=Ni)电子光谱的研究

The UV/VIS spectra for pyridine solution of complexes [Fe_2MO(CH_3COO)_6Py_2]·Py and THF solution of complexes Fe_2MO(CCl_3COO)_6(THF)_3 were studied. The d-d transitions were assigned and the ligand field parameters(B,D_q,β) were calculated for the related metal ions according to ligand field theory (Tanabe-Sugano diagram) in terms of O_h symmetry and reasonably good fits were obtained for the calculated and observed frequencies. The calculated results show that (1) the larger the ionic potential for M~(2+) ion, the larger the values of B, D_q for Fe~(3+) ion (2) the ligand field parameters of metal ions vary in parallel with the electronagativity of R in RCOO~-.     

Ion-Exchange Processes M(II) → Fe(III) and Fe(III) → M(II) in Metal Hexacyanoferrate(II) Gelatin-Immobilized Matrices (M = Mn,Co, Ni,Cu, Zn,Cd)

Ion-exchange reactions M²⁺ Fe³⁺ and Fe³⁺ M²⁺ (M = Mn, Co, Ni, Cu, Zn, Cd) were studied in metal(II) hexacyanoferrate(II) gelatin-immobilized matrices M₂[Fe(CN)₆] in contact with aqueous FeCl₃ solutions and Fe₄[Fe(CN)₆]₃ in contact with aqueous MCl₂ solutions. It was shown that in both cases, M²⁺ was replaced by Fe³⁺ and Fe³⁺ was replaced by M²⁺ to some extent, but no complete replacement was observed in the M₂[Fe(CN)₆]–FeCl₃ or Fe₄[Fe(CN)₆]₃–MCl₂ systems under study. No electrophilic substitution Fe³⁺ Mn²⁺ was found to occur in any noticeable degree during the contact of Fe₄[Fe(CN)₆]₃ with aqueous MnCl₂ solutions even when this contact occurred for 1 h and longer.     

过渡金属M (M=Cu,Ag, Au)对X…Cl (X = F,Cl, Br)卤键相互作用强度的影响

采用量子化学方法,通过MCH2X…ClF(M=Cu,Ag,Au;X=F,Cl,Br)和CH3X…ClF两类复合物的对比,探讨了过渡金属对卤键相互作用强度的影响.CH3X…ClF复合物只有卤键相互作用,而优化MCH2X…ClF复合物除了得到一种只含有卤键相互作用的构型外,还得到一种含有过渡金属和Cl原子相互作用的稳定构型.含有过渡金属的复合物稳定性明显增加,Ag取代的复合物稳定性增加最为明显,Cu次之,Au最不明显.X原子最负分子表面静电势(MEP)减小是复合物稳定性增加的根本原因.利用自然键轨道(NBO)及分子中原子(AIM)分析进一步对体系的分子间相互作用进行了探讨.二阶稳定化能与键鞍点处拓扑性质的计算结果与相互作用能符合得很好.     

Syntheses and X-ray Characterization of Novel [M4(H2O)2(XW9O34)2] n− (M=CuII, X=CuII; and M=FeIII, X=FeIII) Polyoxotungstates

Two novel examples of sandwich type heteropolyanions were synthesized and characterized by X-ray crystal structure and elemental analysis as well as infrared spectroscopy. Na₁₃[H₃Cu₄(H₂O)₂(CuW₉O₃₄)₂]39H₂O (1) and Na₉K[Fe₄(H₂O)₂(FeW₉O₃₄)₂]32H₂O (2) were prepared in aqueous solution by reaction of sodium tungstate with Fe^III and Cu^II cations, respectively. 1 crystallizes in the monoclinic space group P2₁/n (a=13.054(3) Å, b=17.729(4) Å, c=20.998(4) Å, =93.50(3)°), while 2 is triclinic, space group P¯1 (a=12.316(2) Å, b=13.716(3) Å, c=14.925(3) Å, =99.36(3)°, =104.21(3)°, =101.55(3)°). Each anion consists of two [XW₉O₃₄] ^n– moieties (X=Fe^III, n=11 (1) and Cu^II, n=12 (2)) which can be described as -B-isomers of the defect Keggin anion. These units are linked via a belt of four Fe^IIIO₆ or Cu^IIO₆ groups. Two transition metal atoms fill their octahedral coordination sphere with one additional water ligand.     

Tunability of the M(II)M(III)/M(II)(2) and M(III)(2)/M(II)M(III) (M=Mn, Co) couples in bis-μ-O,O'-carboxylato-μ-OR bridged complexes

A comparison of the electrochemical properties of a series of dinuclear complexes [M(2)(L)(RCO(2))(2)](+) with M = Mn or Co, L = 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) or 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato (bpbp(-)) and R = H, CH(3), CF(3) or 3,4-dimethoxybenzoate demonstrates: (i) The electron-withdrawing sulfonyl groups in the backbone of bpsmp(-) stabilize the [M(2)(bpsmp)(RCO(2))(2)](+) complexes in their M(II)(2) oxidation state compared to their [M(2)(bpbp)(RCO(2))(2)](+) analogues. Manganese complexes are stabilised by approximately 550 mV and cobalt complexes by 650 mV. (ii) The auxiliary bridging carboxylato ligands further attenuate the metal-based redox chemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300-400 mV. Within the working potential window, reversible or quasi-reversible M(II)M(III)? M(II)(2) processes range from 0.31 to 1.41 V for the [Co(2)(L)(RCO(2))(2)](+/2+) complexes and from 0.54 to 1.41 V for the [Mn(2)(L)(RCO(2))(2)](+/2+) complexes versus Ag/AgCl for E(M(II)M(III)/M(II)(2)). The extreme limits are defined by the complexes [M(2)(bpbp)(CH(3)CO(2))(2)](+) and [M(2)(bpsmp)(CF(3)CO(2))(2)](+) for both metal ions. Thus, tuning the ligand field in these dinuclear complexes makes possible a range of around 0.9 V and 1.49 V for the one-electron E(M(II)M(III)/M(II)(2)) couple of the Mn and Co complexes, respectively. The second one-electron process, M(II)M(III)? M(III)(2) was also observed in some cases. The lowest potential recorded for the E°(M(III)(2)/M(II)M(III)) couple was 0.63 V for [Co(2)(bpbp)(CH(3)CO(2))(2)](2+) and the highest measurable potential was 2.23 V versus Ag/AgCl for [Co(2)(bpsmp)(CF(3)CO(2))(2)](2+).     

钛,锆和铪羰基化合物M(CO)_n(M=Ti,Zr,Hf;n=4～7)的理论研究

利用密度泛函方法对标题化合物的平衡几何、热化学及振动频率进行了理论预测,发现这3种金属原子都有相似的M(CO)n(n=4～7)结构.全局最低构型对M(CO)7都是单态C3v戴帽八面体7S-1,对M(CO)6都是三重态D3d畸变八面体6T(而对应的单重态M(CO)5仅比它低不到21 kJ·mol-1).对M(CO)n(n=5,4)都是三重态6S-1,其构型分别为从6T中移去1个或2个CO基的衍生物5T和4T.此外,五重态的D3h的三角双锥M(CO)5和单态的Td四面体M(CO)4以及能量更高的含有C和O同时与金属成键的独特配位CO基的M(CO)6和M(CO)3也被发现.最后,给出M(CO)7→M(CO)6+CO反应的离解能.并讨论了金属18价电子的Ti(CO)7存在的可能性.