Kristallstruktur von Monosilber(I)amidosulfat,AgSO3NH2

A crystal structure analysis of the colourless AgSO₃NH₂ was carried out at room temperature:M=203.95, orthorhombic, Pcab,a=7.809 (2) Å,b=8.067 (2) Å,c=11.682 (3) Å,V=735.9 ų,Z=8,d _x=3.681 Mgm^–3,F(000)=760, Mo K, =0.71069 Å (graphite monochromator), =5.77 mm^–1,R=4.36% (509 reflections, 56 parameters). The ionic structure shows approximate trigonal bipyramidal coordination around the Ag⁺-ions.

     

A Novel Three-Dimensional Copper(II) Complex Linked by Covalent and Hydrogen Bonds: [Cu2(L)(PDC)2(H2O)2]...12H2O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane, PDC = 2,3-pyrazinedicarboxylate)

A new compound [Cu₂(L)(PDC)₂(H₂O)₂]...12H₂O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]doco-sane, PDC = 2,3-pyrazinedicarboxylate) was prepared and its structure was determined by X-ray diffraction method. Complex 1 crystallizes in the monoclinic space group P2₁/c with a = 15.653(2) Å, b = 9.879(2) Å, c = 15.202(2) Å, = 98.98(1)°, V = 2321.9(6) ų, and Z = 2. Each copper atom in complex 1 reveals an axially elongated octahedral geometry with an inversion center. Magnetic susceptibility measurement shows a weak ferromagnetic interaction between two Cu(1) and Cu(2) centers with a J value of +0.12 cm^-1. The intermolecular hydrogen–bonding interaction gives rise to a three-dimensional network.     

On the crystal chemistry of three copper(II)-arsenates: Cu3(AsO4)2-III,Na4Cu(AsO4)2, and KCu4(AsO4)3

The three copper(II)-arsenates were synthesized under hydrothermal conditions; their crystal structures were determined by single-crystal X-ray diffraction methods:Cu₃(AsO₄)₂-III:a=5.046(2) Å,b=5.417(2) Å,c=6.354(2) Å, =70.61(2)°, =86.52(2)°, =68.43(2)°,Z=1, space group ,R=0.035 for 1674 reflections with sin / 0.90 Å^–1.Na₄Cu(AsO₄)₂:a=4.882(2) Å,b=5.870(2) Å,c=6.958(3) Å, =98.51(2)°, =90.76(2)°, =105.97(2)°,Z=1, space group ,R=0.028 for 2157 reflections with sin / 0.90 Å^–1.KCu₄(AsO₄)₃:a=12.234(5) Å,b=12.438(5) Å,c=7.307(3) Å, =118.17(2)°,Z=4, space group C2/c,R=0.029 for 1896 reflections with sin / 0.80 Å^–1.Within these three compounds the Cu atoms are square planar [4], tetragonal pyramidal [4+1], and tetragonal bipyramidal [4+2] coordinated by O atoms; an exception is the Cu(2)^[4+1] atom in Cu₃(AsO₄)₂-III: the coordination polyhedron is a representative for the transition from a tetragonal pyramid towards a trigonal bipyramid. In KCu₄(AsO₄)₃ the Cu(1)^[4]O₄ square and the As(1)O₄ tetrahedron share a common O—O edge of 2.428(5) Å, resulting in distortions of both the CuO₄ square and the AsO₄ tetrahedron. The two Na atoms in Na₄Cu(AsO₄)₂ are [6] coordinated, the K atom in KCu₄(AsO₄)₃ is [8] coordinated by O atoms.Die drei Kupfer(II)-Arsenate wurden unter Hydrothermalbedingungen gezüchtet und ihre Kristallstrukturen mittels Einkristall-Röntgenbeugungsmethoden ermittelt:Cu₃(AsO₄)₂-III:a = 5.046(2) Å,b = 5.417(2) Å,c = 6.354(2) Å, = 70.61 (2)°, = 86.52(2)°, = 68.43(2)°,Z = 1, Raumgruppe ,R = 0.035 für 1674 Reflexe mit sin / 0.90 Å^–1.Na₄Cu(AsO₄)₂:a = 4.882(2) Å,b = 5.870(2) Å,c = 6.958(3) Å, = 98.51(2)°, = 90.76(2)°, = 105.97(2)°,Z = 1, Raumgruppe ,R = 0.028 für 2157 Reflexe mit sin / 0.90 Å^–1.KCu₄(AsO₄)₃:a = 12.234(5) Å,b = 12.438(5) Å,c = 7.307(3) Å, = 118.17(2)°,Z = 4, Raumgruppe C2/c,R = 0.029 für 1896 Reflexe mit sin / 0.80 Å^–1.Die Cu-Atome in diesen drei Verbindungen sind durch O-Atome quadratisch planar [4], tetragonal pyramidal [4 + 1] und tetragonal dipyramidal [4 + 2]-koordiniert; eine Ausnahme ist das Cu(2)^{[4 + 1]}-Atom in Cu₃(AsO₄)₂-III: Das Koordinationspolyeder stellt einen Vertreter des Übergangs von einer tetragonalen Pyramide zu einer trigonalen Dipyramide dar. In KCu₄(AsO₄)₃ haben das Cu(1)^[4]O₄-Quadrat und das As(1)O₄-Tetraeder eine gemeinsame O—O-Kante von 2.428(5) Å, was eine Verzerrung der beiden Koordinationsfiguren CuO₄-Quadrat und AsO₄-Tetraeder bedingt. Die zwei Na-Atome in Na₄Cu(AsO₄)₃ sind durch O-Atome [6]-koordiniert, das K-Atom in KCu₄(AsO₄)₃ ist [8]-koordiniert.

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Zur Kristallchemie dreier Kupfer (II)-Arsenate: Cu₃(AsO₄)₂-III, Na₄Cu(AsO₄)₂ und KCu₄(AsO₄)₃

     

Two clathrates of bis(isothiocyanato)tetrakis(4-methylpyridine)magnesium(II) as a host with 4-methylpyridine as a guest

Two clathrate modifications of the title host with 4-methylpyridine (4-CH₃C₅H₄N) as a guest have been determined at –50°C. [Mg(4-CH₃C₅H₄N)₄(NCS)₂] · 2/3(4-CH₃C₅H₄N) · 1/3H₂O is trigonal, space group , witha=27.630(7),c=11.219(3) ÅV=7417(4) ų,Z=9,D _calc=1.171 g cm^–3,(CuK )=18.506 cm^–1, finalR=0.064. [Mg(4-CH₃C₅H₄N)₄(NCS)₂] · (4-CH₃C₅H₄N) is tetragonal, space group I4_l/a, witha=16.944(7),c=23.552(9)Å,V=6762(5) Å,Z=8,D _calc=1.191 g cm^–3, (CuK )=18.200 cm^–1, finalR=0.071.The structures consist of molecular packings of the same host complex units and the guest species. The Mg(II) cation is octahedrally coordinated to theN-atoms of four 4-methylpyridine and twotrans-coordinated isothiocyanato ligands in the host molecule. The conformations of the molecule are considerably different both in symmetry and in geometry in these two structures. The guest 4-methylpyridine molecules are disordered into channels which have different topology in these two clathrates resulting in different thermal stability.     

Molecular structure of the cobalt(ii) chloride complex with triphenyl-N-(2-pyrimidyl)phosphineimine

An X-ray structural study of the cobalt(ii) chloride complex with triphenyl-N-(2-pyrimidyl)phosphineimine has been performed (automatic diffractometer, Mo-–K , 2916 observed reflections, the heavy-atom method, the least squares method in anisotropicisotropic approximation toR=0.043). The crystals are monoclinic,a=15.979(6) Å,b=17.391(6) Å,c=14.976(6) Å, =104.21(2)°,V=4034(5) ų,d _calc=1.384 g cm^–3,Z=4, space groupP2₁/c. The Co atom has a distorted tetrahedral coordination by two Cl atoms (2.268(2) Å and 2.278(3) Å) and two N atoms (2.030(4) Å and 2.025(5) Å) of the two pyrimidine heterocycles. The Cl-Co-Cl and N-Co-N bond angles are equal to 107.7(1)° and 123.4(2)°, respectively. Additional weak coordination of the Co atom by two N atoms of the imine groups [Co...N 2.982(4) Å and 3.045(4) Å] is also observed in the molecule of the complex, and this coordination changes the nearest environment of the Co atom to distorted octahedral coordination. The lengths of the phosphorus-imine P=N bonds are 1.596(6) Å and 1.585(6) Å. The results obtained are compared with previous structural investigations of similar complexes of transition metals with iminophosphoranes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1203–1206, July, 1993.     

Kristallstruktur von Trisilber(I)amidosulfat-3-Ammoniak-2-Wasser,Ag3SO3N · 3NH3 · 2H2O

An X-ray crystal structure analysis of colourless Ag₃SO₃N · 3NH₃ · 2H₂O was carried out at room temperature:M=504.79, orthorhombic, P2₁2₁2₁,a=6.275 (1) Å,b=11.826 (2) Å,c=14.299 (12) Å,V=1061.10 ų,Z=4,d _x=3.160 Mgm^–3,F(000)=940, Mo K, =0.71069 Å (graphite monochromator), =5.60 mm^–1,R=4.71%,R _w=4.96% (982 reflections, 120 parameters). The structure consists of Ag ribbons; each Ag atom is linearly co-ordinated to two N atoms with distances corresponding to covalent Ag-N bonds; no Ag-O coordination is observed; the N atom of the SO₃N group is surrounded by three Ag atoms; compared to amidosulfuric acid, the SO₃N group shows significant deformation.

     

Coordination chemistry of alkali and alkaline earth cations: Synthesis and crystal structure of potassium(benzo-15-crown-5)2 [3,5-dinitrobenzoate(3,5-dinitrobenzoic acid)2]

The interaction of K(35-Dnb) (35-Dnb=3,5-dinitrobenzoate) with benzo-15-crown-5 (B15C5) in ethanol yields a charge-separated sandwich structured complex [K(B15C5)₂]⁺[35-Dnb(35-DnbH)₂]^– even when equimolar amounts of reactants were used and no external 35-DnbH was added to the reaction mixture. The complex (KC₄₉H₅₁O₂₈N₆, FW=1211.1), is monoclinic,P2₁/c,a=11.063(2),b=10.680(1),c=46.548(8) Å, =91.629(2)⁰,Z=4,D ₀=1.485 g/cm³,D _c=1.468 g/cm³, CuK =1.5418 Å, =17.01 cm^–1, 2<130⁰,F(000)=2520,T=298 K. FinalR for the 6618 observed reflections was 0.071. In the sandwich moiety, the K⁺ is 10-coordinated through all the oxygens of the crown molecules (K⁺–O, 2.76–3.11 Å). The 35-Dnb anion lies 5.3 Å below the lower crown mean plane and is charge separated with respect to K⁺ (K⁺–O^–>7 Å) but undergoes strong hydrogen bonding (2.59 and 2.49 Å) through each carboxylate oxygen with the carboxylic protons of two separate 35-DnbH molecules. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82014 (52 pages).     

Structure of the neutral metal complex Pt(dddt)2

A neutral metal complex, [Pt(dddt)₂]° (1), has been obtained by oxidation of the [Pt(dddt)₂]^– anion with excess (Bu₄N)AuBr₄ in nitrobenzene. Crystallographic data for 1a=17.854(9) Å,b=18.409(9) Å,c=4.717(5) Å, =68.83(2)°, space group P2₁/n,Z=4,d _calc=2.55 g/cm³. In1 two independent centrosymmetric [Pt(dddt)₂]° molecules are packed in stacks that form layers parallel to the (110) plane. The molecules of1 in the layers have shortened S...S contacts 3.491(9) Å, and 3.594(10) Å. The average bond lengths Pt-S 2.242(7) Å, S-C 1.71(2) Å and C=C 1.40(3) Å, together with the square-planar coordination of Pt in PtS₄, suggest considerable conjugation in the metal cycles.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1207–1209, July, 1993.     

The synthesis and crystal structure of a cubane-like tungsten copper sulphur cluster, [W4CuS4 2P(OEt)2 3(I)(μ2-PhCO2)(MeCN)]

Summary The title compound [W₃C₃S₄{S₂P(OEt)₂}₃(I)(₂ ^–PhCO₂)(MeCN)] crystallized in triclinic system with space group P1 and cell dimensiona=11.645(6),b=18.565(2),c=11.292(7)Å, =96.15(3)°, =113.65(3)°, =93.77(3)°, V=2207.6ų, Z=2, Mr=1588.09, D_c=2.39 g cm^–3. MoK radiation, =0.71073 Å, =97.3 cm^–1, F(000)=1488, R=0.042 for 5588 observed unique reflections I3(I). There are some distortions in the cubane-like W₃CuS₄ core, with three W-W bonds and three weak W-Cu bonds. Two W atoms are coordinated by PhCO₂ bridge ligand, the other W atom is coordinated to the N atom of MeCN.     

Crystal structures of the organic metals (ET)2[Hg(SCN)Cl2] and (ET)2[Hg(SCN)2Br]

The compositions and structures of two new organic metals based on ET [where ET = bis(ethylenedithio)tetrathiafulvalene], viz., (ET)₂[Hg(SCN)Cl₂], with a metal-dielectric transition temperature (T_m-d) of 35°K, and (ET)₂[Hg(SCN)₂Br], with T_m-d = 140°K, were established by x-ray diffraction analysis. The crystal structures of the investigated compounds are similar to the structure of the previously studied organic metal (ET)₂[Hg(SCN)₂Cl] with T_m-d = 50°K. The principal crystallographic data for (ET)₂[Hg(SCN)Cl₂] are as follows: a = 36.64(1), b = 8.300(4), c = 11.798(1) Å, = 89.91(3)°, V = 3588.1(9) ų, space group Cc, Z = 4, d_calc = 2.05 g/cm³. The principal crystallographic data for (ET)₂[Hg(SCN)₂Br] are as follows: a = 37.088(14), b = 8.338(3), c = 11.738(5) Å, = 89.71(3)°, V = 3629.6(8) ų, space group C2/c, Z = 8, d_calc = 2.15 g/cm³. A characteristic feature of the crystal structure of the investigated compounds is alternation of the anion and cation layers along the a axis of the crystal. In the cation layer of the k type the ET are interconnected by shortened S...S intermolecular contacts (3.39–3.58 Å). The [Hg(SCN)_3–nX_n]^– anions (X = Cl, Br; n = 1, 2) form polymeric chains with one or two bridged SCN groups. A tendency for a decrease in the metal-dielectric transition temperature with a decrease in the volume of the anion is detected in the (ET)₂[Hg(SCN)_3–nX_n] salts, where X = Cl and Br, and n = 1 and 2.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2323–2331, October, 1992.     

Kristallstruktur von Trisilber(I)amidosulfat Monohydrat,Ag3SO3N · H2O

An X-ray crystal structure analysis of yellow Ag₃SO₃N · H₂O was carried out at room temperature:M=435.69, monoclinic, P2₁/n,a=11.628 (5) Å,b=8.058 (4) Å,c=12.034 (5) Å, =86.49 (3)°,V=1125.5 ų,Z=8,d _x =5.142 Mgm^–3, MoK, =0.71069 Å (graphite monochromator), =10.5 mm^–1,R=5.44%,R _w =5.85% (877 reflections, 118 parameters). The structure contains Ag planes with Ag-Ag distances shorter than in metallic silver. The nitrogen atoms of the SO₃N anion are covalently bonded to 4Ag atoms of these Ag planes, thus assuming the extraordinary coordination number of 5. The five crystallographically independent Ag atoms forming the Ag planes have approximate linear N-Ag-N coordination. In addition, the structure contains two Ag atoms which are ionically coordinated to 4 resp. 5O atoms of SO₃N and water. The colour-structure correlation of Ag(I) compounds with colourless anions is discussed.

Herrn Prof. Dr. mult.V. Gutmann zum 65. Geburtstag gewidmet.     

Tetrakis(Isothiocyanato)zinc(II) 4,7,13,16,21,24-Hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane: Synthesis and Crystal Structure

The salt tetrakis(isothiocyanato)zinc(II) 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane, [H₂(Crypt-222)]²⁺ · [Zn(NCS)₄]^2– (I), was synthesized and its structure was determined using X-ray diffraction analysis: space group P2₁/n, a = 13.734 Å, b = 11.627 Å, c = 20.816 Å, = 91.51°, Z = 4. The structure was solved by direct methods and anisotropically refined by the full-matrix least-squares method to R =0.093 for 4920 independent reflections (CAD4 autodiffractometer, CuK radiation). The structural units of crystal I are 2.2.2-cryptand dications (with two protonated nitrogen atoms) and complex anions [Zn(NCS)₄]^2–. The coordination polyhedron of the Zn²⁺ cation is a distorted tetrahedron. The 2.2.2-cryptand dication contains trifurcate N–H(...O)₃ hydrogen bonds.     

Coordination chemistry of alkali and alkaline earth cations. Barium-crown encapsulation studies: The synthesis and crystal structure of barium(picrate)2(benzo-15-crown-5) monohydrate

The interaction of barium with benzo-15-crown-5 (B15C5) has been followed under the competitive effect of various chelating organic anions (L), nitrophenolates and nitrobenzoates, in ethanol and ethanol-water (9:1). The rather heavily hydrated BaL₂ salts yield novel 1:1 stoichiometric products in monohydrated or anhydrous states. Use of excess crown does not under any condition lead to the formation of 1:2 charge separated complexes, expected in view of the cavity and the cation sizes. The 1:1 Ba–B15C5 interaction is counteracted by L in accordance with its nucleophilicity, i.e., the pK _a value of its parent acid, HL. The complex Ba(picrate)₂(B15C5)·H₂O (BaC₂₆H₂₆N₆O₂₀, FW=879.0), is monoclinic,P2₁/c,a=11.43(1),b=16.31(3),c=17.38(2) Å, =92.265(3)°,Z=4,D _c=1.77 g/cm³,D ₀=1.73 g/cm³, MoK, =0.71069 Å, 2 (4.0–50°), =13.5 cm^–1,F(000)=1752,T=–32°C. FinalR for the 5926 reflections was 0.049. The structure reveals barium to be 10-coordinated through all the five crown oxygens (Ba–O, 2.800 to 3.002 Å), the two bidentate picrates (Ba–O, 2.642 and 2.666 Å; Ba–ONO, 2.825 and 2.994 Å), and the water molecule (2.711 Å) so that the cation constitutes a pseudo-sandwich of the crown on one side and the anionic species on the other. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82007 (50 pages). To obtain copies, see page ii of this issue.     

[Pd(NH3)4][IrBr6] Complex: Synthesis,X-ray Powder Diffraction Analysis,and Thermal Decomposition

The complex salt [Pd(NH₃)₄][IrBr₆] was synthesized and studied using X-ray powder diffraction, thermal and elemental analyses, and IR and Raman spectroscopy methods. Crystallographic parameters: a= 11.999 Å, b= 11.290 Å, c= 10.802 Å, V= 1463.3 ų, Z= 4, space group Cmca, (calcd) = 3.841 g/cm³. Thermolysis in an inert atmosphere runs through four stages to yield an equiatomic Pd–Ir solid solution as the final product.     

Synthesis and characterization of new nitridotechnetium-EDTA complex

TcN-EDTA has been synthesized for the first time starting from TcNCl₄ ^–. Elemental analysis shows that this compound has three molecules of water of crystallization: TcN(Hedta) · 3H₂O. Its optical spectrum has an absorption maximum at 505 nm with = 1060 dm³.mol^–1.cm^–1. It decomposed easily under alkaline conditions.     

Two-Dimensional Supramolecular from the Self-Assembly of Dissymmetrical Oxamidato-Bridged Heterometallic Trinuclear Building Blocks: Synthesis, Crystal Structure, and Magnetic Properties

Two heterometallic trinuclear complexes {[Cu(oxbp)]₂Co(H₂O)₂}1.5DMF0.5H₂O (complex 1) and {[Cu(oxbm)]₂Co(H₂O)₂}2DMF (complex 2) were obtained from the self-organization of two new dissymmetrical oxamidato-bridged copper(II) building blocks [Cu(oxbp)]^– and [Cu(oxbm)]^–[H₃oxbp=N-benzoato-N'-(3-aminopropyl)oxamido, H₃oxbm=N-benzoato-N'-(2-amino-2-methylethyl)oxamido, DMF=dimethylformamide]. The crystal structure of complex 1 has been determined. Complex 1 crystallize in triclinic system, space group P-1, a=8.0609(16) Å, b=10.661(2) Å, c=22.279(5) Å, =85.32(3), =86.64(3), =70.90(3), and Z=1. The crystal structure of complex 1 consists of neutral trinuclear complex units, and hydrogen bond involved DMF and water molecules. Through the hydrogen bonds, weak coordination and CuCu weak interactions, complex 1 features a 2-D supramolecular structure. Magnetic susceptibility measurements (5–100 K) indicate that the central Co(II) and terminal copper metal ions are antiferromagnetically coupled with J=–28.09 and J=–29.70 cm^–1 for complex 1 and 2, respectively.     

Crystal structure of copper(II) bis-hexafluoroacetylacetonate

An X-ray diffraction investigation has performed for copper(II) bis-hexafluoroacetylacetonate (Bruker AXS P4 automatic diffractometer, MoK radiation, t = –25°C). Crystal data for C₁₀H₂CuF₁₂O₄: a = 5.530(1) Å, b = 6.038(1) Å, c = 11.266(2) Å, = 95.948(3)°, = 101.743(3)°, = 92.298(3)°, space group; P1, V = 365.6(1) ų, Z = 1, d _calc = 2.169 g/cm³. The square-planar environment of the copper atom (Cu-O_av 1.912 Å, O-Cu-O_av 93°) is completed to bipyramidal by two fluorine atoms of the neighboring molecules, Cu...F 2.71 Å and 2.75 Å.Original Russian Text Copyright © 2004 by S. A. Gromilov, I. A. Baidina, P. A. Stabnikov, and G. V. RomanenkoTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 502–507, May–June 2004.     

Crystal Structure of (2.2.2-Cryptand)lithium Perchlorate

(2.2.2-Cryptand)lithium perchlorate [Li(2.2.2-Crypt)]⁺ClO^– ₄ (I) is prepared and characterized by X-ray structural analysis. Structure I (space group P2₁2₁2, a = 10.149 Å, b = 13.475 Å, c = 8.580 Å, Z = 2) is solved by the direct method and refined anisotropically by the full-matrix least-squares method to R = 0.056 for 2312 reflections (CAD4 automated diffractometer, MoK ). Crystal of complex I is built of [Li(2.2.2-Crypt)]⁺ complex cations of the host–guest type and randomly disordered ClO^– ₄ anions. Both ions are located on the twofold crystallographic axes. The Li⁺ cation, which is also randomly disordered about the 2 axis, is coordinated by the N atom and five O atoms from eight heteroatoms (2N + 6O) of the cryptand. Two Li–O and one Li–N bonds are noticeably elongated. The Li⁺ cation forms irregular six-vertex coordination polyhedron.     

Synthesis,spectral and magnetic studies on mixed-ligand complexes M(DIAFO)2(NCS)2 and M(DIAFH)2X2 (M = FeII,CoII, NiII). The crystal structure of Co(DIAFO)2(NCS)2

Summary A series of mixed-ligand complexes of group VIII metals, M(DIAFO)₂(NCS)₂ and M(DIAFH)₂X₂ (M = Fe^II, Co^II, Ni^II, X = NCS^–, Cl^–) with the 3,3-bridged derivative of 2,2-bipyridyl (bipy) (1) were prepared, where DIAFO (2) and DIAFH (3) are 4,5-diazafluoren-9-one and 4,5-diazafluoren-9-hydrazone, respectively. These complexes were investigated by i.r., u.v.-vis-near i.r. spectroscopy and by variable-temperature magnetic susceptibility measurements. The electronic spectra show that the two ligands exert a field strength far removed from the Fe^II cross-over value. All the complexes are paramagnetic, following the Curie-Weiss law in the 77–300 K range. A typical crystal structure of Co(DIAFO)₂(NCS)₂ for these compounds was determined with orthorhombic, space group Pcan, a = 10.377(5) Å, b = 13.289(6) Å, c= 16.629(7) Å, V = 2293(2) ų, D _c = 1.563 g cm^–3, F(000) = 1091.74, Z = 4, R = 0.043, R = 0.047. Steric effects are thought to be operative in both ligands studied, but are weaker than those of the typical bidentate diimine ligand bipy.Author to whom all correspondence should be directed.     

Crystal and molecular structures of heteroligand bis(hexafluoroacetylacetonato)copper(II) complexes with 3-imidazoline nitroxyl radicals,Cu(C5HF6O2)2:L=1:1 (L1=C13H18N3O,L2=C8H15N2O)

Crystal structures were determined for two new derivatives of heteroligand complexes of Cu(C₅HF₆O₂)₂ with nitroxyl radicals derived from 3-imidazoline: Cu(C₅HF₆O₂)₂(C₁₃H₁₈N₃O) (I) and Cu(C₅HF₆O₂)₂(C₈H₁₅N₂O) (II). The unit cell parameters for I are as follows: a=10.555(3), b=15.505(5), c=18.509(6) Å, V = 3029(1) ų, Z=4, d_calc=1.57 g/cm³, space group P2₁2₁2₁. The unit cell parameters for II are as follows: a=16.018(3), b=15.886(3), c=19.665(4) Å, V = 5004(1)ų, Z=8, d_calc=1.68 g/cm³, d_exp=1.68 g/cm³, space group P2₁2₁2₁. The structure of I is molecular. The coordination of the copper ion is a trigonal bipyramid formed by two oxygen atoms of the (hfac) ions and the nitrogen atom of the imidazoline heterocycle in the equatorial plane [Cu–O, 1.91(7), 2.242(7) Å, Cu–N, 2.010(7) Å] and the other oxygen atoms of the (hfac) anion in the axial positions [Cu–O, 1.940(6), 1.963(6) Å]. Complex II is polymeric. The two crystallographically independent Cu(hfac)₂ fragments are linked in a chain by means of two L² ligands. The coordination of the copper ions is a square bipyramid, whose equatorial plane is formed by the oxygen atoms of the (hfac) anion [Cu–O, 1.89(1)–2.03(1) Å]. The axial positions are occupied by nitrogen atoms [Cu–N, 2.52(1), 2.40(1) Å] and an oxygen atom of the NO fragment [Cu–O, 2.96(1), 2.67(1) Å] of different L² ligands. The ...Cu(hfac)₂–L²–Cu(hfac)₂–L₂... chains in the unit cell are located at two levels (x1/4 and 3/4).Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 126–133, March–April, 1993.