若干镧系络合物的空间群

摘要 藉助模拟强度精修将九个镧系络合物晶体结构的空间群作了修正 .（ 1） NaN[Nd(DMSO)5(H2O)3]Cl3· 3H2O从 P1修正为 P;（ 2） Er(ClO4)3· 6(CH3)2NC(O)N(CH3)2从 P修正为 R;（ 3） Nd(O3SCF3)3· DMF· 6H2O从 P1修正为 R3m;(4)[NaNCCH3][Nd{S2CN(CH2CH3)2}4]从 P修正为 C 2/c;(5)[(CH3)2NCS2]3La· 2DMSO从 Cc修正为 C 2/c;（ 6） Yb(C9H7)2· 2THF从 Cc修正为 C 2/c;（ 7） [(C6H5)3Ge]2Yb· 4THF从 P21修正为 P 2;(8)TlPr(C36H44N4)2从 Pna2,修正为 Pnma;(9)[CuLaSm(C4O4)4(H2O)16]· 2H2O从 P2修正为 P2.（ 8）、（ 9）两个络合物结构从非心修正到有心时,不仅改进了键长与键角值,而且影响到分子结构特征的描述 .     

关于空间群判断失误的札记Ⅱ.P空间群的修正

列举１６ 例按Ｐ１ 解出的晶体结构,其空间群应描述为单斜晶系的Ｃ２／ｃ,并讨论从Ｐ１ 修正为三方的Ｒ３ 和四方的Ｉ４１／ａ 的晶体结构各１ 例。分析揭示判断失误的线索。最后强调在结构报告中完整发表原子坐标数据的重要意义。     

关于空间群判断失误的札记Ⅲ.P1空间群的修正

8个原报道属于 P 1的晶体结构应修正为对称性较高的空间群。其中 5例改变晶系和劳埃群 :4例改为 2 / m而另 1例改为 4 / m。余 3例从 P1更正为 P1,对于其中的1个结构利用原始强度数据进行了最小二乘结构再精修。     

关于空间群判断失误的札记Ⅱ. P(S)空间群的修正

列举16例按P(S)解出的晶体结构,其空间群应描述为单斜晶系的C2/c,并讨论从P(S)修正为三方的R(S)和四方的I41/a的晶体结构各1例.分析揭示判断失误的线索.最后强调在结构报告中完整发表原子坐标数据的重要意义.     

关于空间群判断失误的扎记 V.晶系不变情况下的非心群修正

我们发表胡盛志教授的“札记” ,一是想提醒晶体结构工作者们在晶体结构测定过程对空间群的指定应十分小心 ,尽量减少差错 ;同时也想借此透露一些国外同行在纠正空间群测定差错这一方面的工作 ,引起国内同行关注和响应。至于胡教授“札记”的论证方法的客观性 ,论据的充分性等 ,因纯系个人的见解 ,十分欢迎有不同意见者结合实例来稿进行讨论。     

根据计算结构因子重新指定镍(II)8-羟基喹啉的两个络合物(英文)

晶体学研究曾认为分子式是NaNiQ2HQCLO4的结构并不含有钠而应为H3ONiQCLO4.相似地,稀土-Ni络合物YQHQ2NiQ3CLO4也不含有钇而应为H3ONi2Q3CLO4.晶体结构描述的修正系根据文献报导的原子坐标计算结构因子所导出的结果.     

关于空间判断失误的扎记Ⅳ.单斜晶系:从非心到有心空间群

报道了 12个从单斜无心修正为单斜有心的晶体结构。其中 1例从C2修正到C2 /m ,2例从P2 1 到P2 1 /c。 9例从Cc到C2 /c ,除Cc修正到C2 /c的 6例已见诸文献外 ,列出其余 6例在较高对称空间群下的原子坐标     

关于空间群判断失误的札记：Ⅱ.P^—1空间群的修正

列举１６例按Ｐ＾－１解出的晶体结构,其空间群应描述为单斜晶系的Ｃ２／ｃ,并讨论从Ｐ＾－１修正为三方的Ｐ＾－３和四方的Ｉ４１／ａ的晶体结构各１例。分析揭示判断失误的线索。最后强调在结构报告中完整发表原子坐标数据的重要意义。     

CTMAB存在下钪多元络合物的研究

本文系统研究了在阳离子表面活性剂存在下钪与溴邻苯三酚红及三乙烯四胺形成多元络合物的条件，测定了络合物的最大吸收波长和摩尔吸光系数，确定了络合物的组成。并初步探讨了反应机理。     

根据计算结构因子重新指定镍(II)8-羟基喹啉的两个络合物

晶体学研究曾认为,分子式是Na[NiQ2(HQ)](CLO4)的结构并不含有钠而应为[H3O][NiQ2(HQ)](CLO4).相似地,稀土－Ni络合物[YQ(HQ)2][NiQ3](CLO4)也不含有钇而应为[H3O][Ni2Q3(HQ)3](CLO4).晶体结构描述的修正系根据文献报导的原子坐标计算结构因子所导出的结果.     

Crystalline Structure and Electroconductivity of Solid Electrolytes Li3.75Ge0.75V0.25O4 and Li3.70Ge0.85W0.15O4

Crystalline structure of low- and high-temperature modifications of solid lithium-conducting electrolytes Li_3.75Ge_0.75V_0.25O₄ and Li_3.70Ge_0.85W_0.15O₄ are studied by powder neutron diffraction analysis with use made of Rietveld full-profile analysis. The structure of either composition is derivative from -Li₃PO₄. The high conductivity of the electrolytes is connected with the presence of interstitial lithium cations, whose positions are occupied but partially. Phase transitions in the electrolytes consist of the leveling of the occupation degrees of these positions and make practically no impact on the rigid cage of the lattice.     

Revising Space Groups from Simulated SHELX·fcf Structure Factors. More Examples of Incorrect Space Groups, an Example of a Chemically-Incorrect Structure and the Special Case of P1 to P(-1) Revisions

The structure factors of any crystal structure can be simulated from its atomic coordinates (and temperature factors) in a SHELXL-97 run on a dummy hkl in which only the scale factor is refined. The squares of the structure factors are retrieved from thefcf, and such simulated data are used in the revision of the space groups of several incorrectly-refined crystal structures. Two cases, a P1 to Pl- revision and a chemically-incorrect structure that is refined in a correct space group, are discussed.     

Reaktionen von Lanthanoidhalogeniden mit Alkalibenzylverbindungen. Darstellung und Kristallstrukturen von [(tmeda)(C6H5CH2)2Y(μ-Br)2Li(tmeda)], [(tmeda)2SmBr(μ-Br)2Li(tmeda)] und [(dme)2SmBr(μ-Br)]2

Reactions of Lanthanide Halides with Alkalibenzyl Compounds. Synthesis and Crystal Structures of [(tmeda)(C₆H₅CH₂)₂Y(μ-Br)₂Li(tmeda)], [(tmeda)₂SmBr(μ-Br)₂Li(tmeda)] and [(dme)₂SmBr(μ-Br)]₂ Alkali-benzyl compounds react via a metathesis reaction with lanthanide halides to benzyl complexes of the rare earths. Reaction of [(C₆H₅CH₂)Li(tmeda)] with YBr₃ leads to the complex [(tmeda)Y(C₆H₅CH₂)₂ (μ-Br)₂Li(tmeda)] 1 , in which Yttrium and lithium are linked via two bromide bridges. However, the reaction of [(C₆H₅CH₂)Li(tmeda)] with SmBr₃ in toluene/tmeda leads under reduction of the Sm ion to the compound [(tmeda)₂SmBr(μ-Br)₂Li(tmeda)] 2 . 2 reacts with DME to yield the dimeric compound [(dme)₂SmBr(μ-Br)]₂ 3 . The structures of 1 – 3 were determined by X-ray single crystal structure analysis:

• 1: Space group P2₁/c, Z = 4, a = 829.5(6) pm, b = 1477.9(11) pm, c = 2575.0(10) pm, β = 92.03(6)°,
• 2: Space group P2₁, Z = 2, a = 954,7(3) pm, b = 1338.5(6) pm, c = 1244.9(5) pm, β = 107.51(3)°,
• 3: Space group P1 , Z = 1, a = 797.2(7) pm, b = 818.3(7) pm, c = 1169.7(8) pm, α = 100.96(6)°, β = 92.03(6)°, γ = 91.75(7)°.

     

Thiocyanate complexes of the group 12 metals with pyridine-2-carboxamide: Synthesis and structural characterization

Three complexes of picolinamide (pyridine-2-carboxamide, pia) and metal thiocyanates, M(SCN)₂, (M = Zn, Cd, Hg), namely two polymorphs of bis(picolinamide-N,O)-bis-(thiocyanato-N)zinc(II) (1a and 1b), catena-[bis(μ-thiocyanato-S,N)-picolinamide-N,O-cadmium(II)] (2) and bis[(μ₂-thiocyanato-S-thiocyanato-S-picolinamide-N,O)mercury(II)] (3) have been prepared and characterized by spectroscopic, thermal and X-ray crystallographic methods. The IR and thermal data correlate with the structures of the complexes in the solid state. The vibration bands of diagnostic value are compared to the values of the free ligands.     

Synthesis and Crystal Structures of Group 10 Metal Bis(dithiolate) Complexes Constructed by 2,3-Naphtho-15-Crown-5 or 2,3-Naphtho-18-Crown-6

Five novel 2,3-naphtho crown ether group 10 metal bis(dithiolate) complexes, [Na(N15C5)₂]₂[Pd(mnt)₂] (1), [Na(N15C5)]₂[Pd(i-mnt)₂] (2) and [K(N18C6)]₂[M(i-mnt)₂] (3 5) (where mnt = 1,2-dicyanoethylene-1,2-dithiolate, i-mnt = 1,1-dicyanoethylene-2,2-dithiolate and M = Ni, Pd, Pt for complexes 3–5, respectively), have been synthesized and characterized by elemental analysis, FT-IR, UV–Visible spectra and single crystal X-ray diffraction. X-ray diffraction analyses reveal that complexes 1 and 2 have different structural features while complexes 3–5 are structurally isomorphous. Complex 1 consists of two [Na(N15C5)₂]⁺ sandwich complex cations and one [Pd(mnt)₂]²⁻ anion, affording a zero-dimensional structure. For 2, the [Na(N15C5)]⁺ mono-capped complex cations act as the bridges linking the [Pd(i-mnt)₂]²⁻ anions into a 1D infinite chain through Na–N interactions and SȮFC and SȮFπ interactions are observed in the resulting chain. Complexes 3–5 all consist of two [K(N18C6)]⁺ complex cations and one [M(i-mnt)₂]²⁻ (M = Ni, Pd or Pt) anion and the complex molecules are linked into␣1D␣chains by the bridging K–O(ether) interactions between the adjacent [K(N18C6)]⁺ units. What’s novel is that the resulting chains are assembled into novel 2D networks through interchain π–π stacking interactions between the neighboring naphthylene moieties of N18C6. The stack model of naphthylene group in complexes 3–5 is discussed.     

Syntheses and Structures of Two Novel Salicylate-containing Mononuclear Manganese Complexes

Two salicylate containing mononuclear manganese complexes formulated as [Mn- (sal)2(CH3OH)2]·py (sal = salicylate, py = pyridine) 1 and (HNEt3)2[Mn(sal)3] 2 have been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction analyses. Crystal data for compound 1: monoclinic, space group C2/c, a = 30.748(6), b = 8.1933(13), c = 21.137(4) °, β = 126.772(4)°, V = 4265.5(13) 3, Z = 8, Mr = 471.34, Dc = 1.468 g/cm3, μ = 0.667 mm-1, F(000) = 1952, the final R = 0.0637, wR = 0.1783 (I > 2σ(I)) and GOOF = 1.073; and those for compound 2: monoclinic, space group C2/c, a = 14.505(5), b = 11.048(4), c = 20.711(7) , β = 103.603(6)°, V = 3225.6 (18) 3, Z = 4, Mr = 668.65, Dc = 1.377 g/cm3, μ = 0.466 mm-1, F(000) = 1416, the final R = 0.0373, wR = 0.1125 (I > 2σ(I)), and GOOF = 1.000. The Mn atoms of both complexes are six-coordinated in an axially elongated octahedral geometry for 1 and an axially compressed octahedral geometry for 2, and their oxidation states have been determined to be trivalent by bond valence sum calculation.