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991.
Liliana Cseh Carol Csunderlik Ingo Pantenburg Gerd Meyer Otilia Costisor 《无机化学与普通化学杂志》2003,629(6):985-988
The complex Co(C14H13NO)2Cl2 with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl2·6H2O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co2+ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed. 相似文献
992.
CoSm(SeO3)2Cl, CuGd(SeO3)2Cl, MnSm(SeO3)2Cl, CuGd2(SeO3)4 and CuSm2(SeO3)4: Transition Metal containing Selenites of Samarium and Gadolinum The reaction of CoCl2, Sm2O3, and SeO2 in evacuated silica ampoules lead to blue single crystals of CoSm(SeO3)2Cl (triclinic, , Z = 4, a = 712.3(1), b = 889.5(2), c = 1216.2(2) pm, α = 72.25(1)°, β = 71.27(1)°, γ = 72.08(1)°, Rall = 0.0586). If MnCl2 is used in the reaction light pink single crystals of MnSm(SeO3)2Cl (triclinic, , Z = 2, a = 700.8(2), b = 724.1(2), c = 803.4(2) pm, α = 86.90(3)°, β = 71.57(3)°, γ = 64.33(3)°, Rall = 0.0875) are obtained. Green single crystals of CuGd2(SeO3)2Cl (triclinic, , Z = 4, a = 704.3(4), b = 909.6(4), c = 1201.0(7) pm, α = 70.84(4)°, β = 73.01(4)°, γ = 70.69(4)°, Rall = 0.0450) form analogously in the reaction of CuCl2 and Gd2O3 with SeO2. CoSm(SeO3)2Cl contains [CoO4Cl2] octahedra, which are connected via one edge and one vertex to infinite chains. The Mn2+ ions in MnSm(SeO3)2Cl are also octahedrally coordinated by four oxygen and two chlorine ligands. The linkage of the polyhedra to chains occurs exclusively via edges. Both, the cobalt and the manganese compound show the Sm3+ ions in eight and ninefold coordination of oxygen atoms and chloride ions. In CuGd(SeO3)2Cl the Cu2+ ions are coordinated by three oxygen atoms and one Cl— ion in a distorted square planar manner. One further Cl— and one further oxygen ligand complete the [CuO3Cl] units yielding significantly elongated octahedra. The latter are again connected to chains via two common edges. For the Gd3+ ions coordination numbers of ?8 + 1”? and nine were found. Single crystals of the deep blue selenites CuM2(SeO3)4 (M = Sm/Gd, monoclinic, P21/c, a = 1050.4(3)/1051.0(2), b = 696.6(2)/693.5(1), c = 822.5(2)/818.5(2) pm, β = 110.48(2)°/110.53(2)°, Rall = 0.0341/0.0531) can be obtained from reactions of the oxides Sm2O3 and Gd2O3, respectively, with CuO and SeO2. The crystal structure contains square planar [CuO4] groups and irregular [MO9] polyhedra. 相似文献
993.
CompoundsformedfromCu ,AgandAuwithdithio lateligands ,suchasthedialkyldithiocarbamate (DTC) ,mercaptothiazoline (HMT)anddialkyldithiophosphates(DDP) ,haveplayedanimportantroleintechnology .1Cu(I) Sclustersalsohavebeenimplicatedinbiologyasan ti oxidants .2Thecuban… 相似文献
994.
995.
石墨炉原子吸收光谱无标样分析法的研究:Ⅰ.消除基体干扰 总被引:1,自引:0,他引:1
实现石墨炉原子吸收光谱绝对分析必须消除基体干扰,本研究采用有机基体改进剂,管壁原子化、热解涂层石墨管,峰面积积分吸收信号,D2灯或Zeeman效应扣除背景,有效地控制和消除了海水基体对As,Cd,Co,Cr,Cu,Mn,Ni,Pb和V等元素的干扰,实现了无干扰测定。 相似文献
996.
A New High Temperature Form of TiO: H? TiO Single crystals of a high temperature form of TiO (H? TiO) were prepared above 3 000°C by CO2-LASER technique. They crystallize with a hitherto unobserved crystal structure of oxides with titanium in the oxidation state two, isotypic to tungsten carbide with Ti2+ in a trigonal prismatic surrounding by oxygen. Space group D–P6 m2, a = 3.0310, c = 3.2377 Å, Z = 1. 相似文献
997.
Michael Ruck 《无机化学与普通化学杂志》1994,620(10):1832-1836
Preparation and Crystal Structure of the First Polymeric Phosphorus Selenide catena-(P4Se4)x Catena-(P4Se4)x was prepared in crystalline form from the elements using iodine as a catalyst, and characterized by means of X-ray diffraction and IR spectroscopy. Single-crystal investigations (space group P21/c, a = 1 119.2(3), b = 728.2(2), c = 1 142.5(3) pm, β = 115.91(2)°, V = 837.5(7) · 106 pm3) revealed parallel chains of P4Se3 hetero-norbornane units linked via Se atoms. Thus, being the first phosphorus selenide which does not contain discrete molecules, catena-(P4Se4)x can be regarded as a polymeric form of α-P4Se4 or as a crystalline modification of vitrous phosphorus selenide. 相似文献
998.
钯镁基体改进剂对铅,铋,锗在石墨炉中原子化影响的研究 总被引:7,自引:0,他引:7
通过原子吸收和X-射线衍射分析证明,加入钯镁基体改进剂在预热处理后对Pb、Bi和Ge三个元素分别生成金属间化合物PbPd_3、BiPd_3、Ge_9Pd_(23)和其他化合物,从而提高了最高允许灰化温度,改变了原子化机理。在原子化阶段这些金属间化合物直接分解为金属原子,结果提高测定灵敏度。 相似文献
999.
Green Bis-(2-iminoisopropyl-thiophenolato)nickel(II) and other Similar NiII Complexes The compounds [NiII(iitp)2] 1 (iitp = 2-iminoisopropyl-thiophenolate), [Ni(imptp)2] · 2 CH3OH 2 , a dinuclear compound with an Ni? Ni distance of 276 pm, and [PPh4] · [NiII(imptp)(SCN)] 3 (imptp = 2-(2-iminopentane-4-on)-thiophenolate) have been prepared by the reaction of nickel(II)-acetate-tetrahydrate with 2-iminoisopropyl-thiophenole and 2-(2-iminopentane-4-on)-thiophenole in methanol, respectively. They have been characterized by single-crystal X-ray structure analysis and other physical methods. The redox behaviour of 1–3 has been studied in detail (chemically as well as by cyclovoltammetry and ESR spectroscopy). Particularly interesting are the electronic properties of 1 and its reduction with NaBH4 and the following reaction of the product with O2. The complexes are model compounds for some Ni-containing enzymes. For details of the crystal structure determination see “Inhaltsübersicht”. 相似文献
1000.
Montserrat Barquín María J. Gonzlez Garmendia Liher Larrínaga Elena Pinilla María R. Torres 《无机化学与普通化学杂志》2005,631(11):2210-2214
The complexes of copper formato with pyrazine and dimethylpyrazines: Cu(HCOO)2(pyrz) ( 1 ), Cu2(HCOO)4(pyrz) ( 2 ), Cu2(HCOO)4(2,3‐Me2pyrz) ( 3 ), Cu2(HCOO)4(2,5‐Me2pyrz) ( 4 ), and Cu2(HCOO)4(2,6‐Me2pyrz)2 ( 5 ) have been synthesized and characterized by chemical analysis and IR and electronic spectro scopies. The three‐dimensional structure of compound 1 consists of –Cu–pyrz–Cu–pyrz– chains joined by bridging formate groups coordinated, in configuration syn‐anti, to two copper atoms. The coordination around the copper atom is orthorhombic with two Cu–O distances of 2.374(1) Å, two Cu–O of 1.952 Å and two Cu–N of 2.080 Å. Compound 5 is formed by molecular dimers with the [Cu2(μ‐HCOO)4] unit, two copper atoms and four syn‐syn fomate groups, and two ligands coordinated to the copper atoms in the axial positions. In compounds 2 and 3 chains of [Cu2(μ‐HCOO)4] dimers with pyrz or 2,3‐Me2pyrz as bridging ligands are formed. The EPR signal of 1 is orthorhombic (g = 2.23, 2.20 and 2.06). In the EPR spectra of 2 – 5 compounds the triplet (S = 1) signals are observed. The g?, g∥ and D values are been calculated. 相似文献