Synthesis and crystal structures of nitratocobaltates Na2[Co(NO3)4], K2[Co(NO3)4], and Ag[Co(NO3)3] and potassium nitratonickelate K2[Ni(NO3)4]

The cobalt(II) and nickel(II) nitrate complexes with an island structure (Na₂[Co(NO₃)₄] (I) and K₂[Co(NO₃)₄] (II)] and a chain structure [Ag[Co(NO₃)₃] (III) and K₂[Ni(NO₃)₄] (IV)] are synthesized and investigated using X-ray diffraction. In the anionic complex [Co(NO₃)₄]^2? of the crystal structure of compound I, the Co coordination polyhedron is a twisted tetragonal prism formed by the O atoms of four asymmetric bidentate nitrate groups. In the anion [Co(NO₃)₄]^2? of the crystal structure of compound II, one of the four NO₃ groups is monodentate and the other NO₃ groups are bidentate (the coordination number of the cobalt atom is equal to seven, and the cobalt coordination polyhedron is a monocapped trigonal prism). The crystal structures of compounds III and IV contain infinite chains of the compositions [Co(NO₃)₂(NO₃)_2/2]^? and [Ni(NO₃)₃(NO₃)_2/2]^2?, respectively. In the crystal structure of compound III, seven oxygen atoms of one monodentate and three bidentate nitrate groups form a dodecahedron with an unoccupied vertex of the A type around the Co atom. In the crystal structure of compound IV, the octahedral polyhedron of the Ni atom is formed by five nitrate groups, one of which is terminal bidentate. The data on the structure of Co(II) coordination polyhedra in the known nitratocobaltates are generalized.     

Crystal structure of a new basic nitrate of neodymium(III), [Nd6O(OH)8(H2O)14(NO3)6](NO3)2 · 2H2O

A new basic Nd³⁺ nitrate, [Nd₆O(OH)₈(H₂O)₁₄(NO₃)₆](NO₃)₂ · 2H₂O (I), is isolated in the crystal form and studied. Compound I differs from the basic Ln nitrates containing [Ln ₆O(OH)₈] clusters in that it involves a larger number of water molecules. The incorporation of additional water molecules is accompanied by changes in the coordination environment of one of the three crystallographically independent Nd³⁺ cations. Two cations have coordination polyhedra in the form of a monocapped tetragonal antiprism with a coordination number of 9, and the third cation has a polyhedron in the form of a bicapped tetragonal antiprism with a coordination number of 10. Original Russian Text ? I.A. Charushnikova, C. Den Auwer, 2007, published in Kristallografiya, 2007, Vol. 52, No. 2, pp. 248–251.     

Synthesis and X-ray diffraction study of (Cs0.5Ba0.25)[UO2(CH3COO)3] and Ba0.5[UO2(CH3COO)3]

Uranyl triacetate complexes (Cs_0.5Ba_0.25)[UO₂(CH₃COO)₃] (I) and Ba_0.5[UO₂(CH₃COO)₃] (II) are synthesized for the first time and their structures are determined by X-ray diffraction. Both compounds crystallize in the cubic crystal system. The crystal data are as follows: a = 17.3289(7) ?, V = 5203.7(4) ?³, space group I2₁3 and Z = 16 (I); a = 17.0515(8)?, V = 4957.8(4) ?³, space group I $ \bar 4 $ \bar 4 3d, and Z = 16 (II). In I and II, as in all uranyl triacetates studied earlier, the coordination polyhedron of the uranium atom is a hexagonal bipyramid whose vertices are occupied by the oxygen atoms of the uranyl and three acetate groups. The uranium-containing group belongs to the AB ₃⁰¹ (A = UO₂²⁺, B ⁰¹ = CH₃COO⁻) crystal chemical group of uranyl complexes. It was found that compound II is isostructural to the (Rb_0.50Ba_0.25)[UO₂(CH₃COO)₃] studied earlier.     

Crystal structure of PbUO2(CH3COO)4(H2O)3

Single crystals of PbUO₂(CH₃COO)₄(H₂O)₃ have been investigated by X-ray diffraction (R = 0.029 for 3175 reflections). The structure of this compound is formed by [Pb(CH₃COO)(H₂O)₃]⁺ chains, which are oriented along the [100] axis and limited by one-core complexes [UO2(CH₃COO)₃]⁻. The coordination numbers of the Pb(II) and U(VI) atoms are 8, and the coordination polyhedron of uranium is a hexagonal bipyramid whose vertices contain oxygen atoms of three bidentate cyclic acetate groups and the uranyl group. Taking into account the different crystallographic roles of acetate ions, the crystal-chemical formula of [PbUO₂(CH₃COO)₄(H₂O)₃] chains can be written as AA′B ²¹ B ¹¹(B ⁰¹)₂ M ₃¹, where A = Pb; A′ = UO₂²⁺; M ¹ = H₂O; and B ²¹, B ¹¹, and B ⁰¹ are CH₃COO⁻ groups.     

Synthesis and crystal structure of (NH4)3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)]

Single crystals of the compound (NH₄)₃[UO₂(CH₃COO)₃]₂[UO₂(CH₃COO)(NCS)₂(H₂O)] (I) are synthesized, and their structure is investigated using X-ray diffraction. Compound I crystallizes in the monoclinic system with the unit cell parameters a = 18.3414(6) ?, b = 16.3858(7) ?, c = 12.4183(5) ?, β = 92.992(1)°, space group C2/c, Z = 4, V = 3727.1(3) ?³, and R = 0.0253. The uranium-containing structural units of crystals I are mononuclear complexes of two types with an island structure, i.e., the [UO₂(CH₃COO)₃]⁻ anionic complexes belonging to the crystal-chemical group (AB ₃⁰¹ = UO₂²⁺, B ⁰¹ = CH₃COO⁻) of the uranyl complexes and the [UO₂(CH₃COO)(NCS)₂(H₂O)]⁻ anionic complexes belonging to the crystal-chemical group AB ⁰¹M₃¹ (A = UO₂²⁺, B ⁰¹ = CH₃COO⁻, M ¹ = NCS⁻ or H₂O).     

Synthesis, spectroscopic characterisation and X-ray structure of [trans-Co(en)2(NO2)2]2(Cr2O7)

Dark red crystals of bis[trans-dinitrobis(ethylenediamine)cobalt(III)] dichromate, [trans-Co(en)₂(NO₂)₂]₂(Cr₂O₇) have been obtained by slowly allowing to mix the solutions of potassium dichromate and trans-dinitrobis(ethylenediamine)cobalt(III) nitrate in 1:2 molar ratio in aqueous medium. Elemental analyses and spectroscopic techniques (IR, UV/visible, ¹H and ¹³C NMR) were used for characterizing the complex salt. The complex salt crystallizes in the orthorhombic space group Fdd2 with unit cell dimensions a = 24.778(2) ?, b = 30.457(2) ?, c = 6.5364(5) ?, Z = 8, V = 4932.8(7) ?³, R₁ = 0.0617 and wR₂ = 0.1518. X-ray structure determination revealed an ionic structure consisting of cationic cobaltammine [trans-Co(en)₂(NO₂)₂]NO₃ and dichromate anion. It is the first crystal structure of this cation with a dianion.     

Syntheses, Characterizations and Crystal Structures of Two Copper Coordination Polymers Both Having Cu2Cl2 Bridging Subunit [CuI(bipy)1/2Cl]n(1) and {[(CuII)4(phen)4(SSA)2Cl2](H2O)2(DMF)2}n(2)

Abstract  

Two copper coordination polymers [Cu^I(bipy)_1/2Cl] _n (1) and {[(Cu^II)₄(phen)₄(SSA)₂Cl₂] (H₂O)₂(DMF)₂} _n (2)(bipy = 4,4′-bipyridine, phen = 1,10-phenanthroline, H₃SSA = 5-sulfosalicylic acid, DMF = N,N-dimethylformamide) have been prepared and characterized by X-ray diffraction, elemental analysis, IR spectrum and 2 was also studied by cyclic voltammetric method. X-ray analysis indicates that both of them have Cu₂Cl₂ bridging subunit. Complex 1 is a two dimensional network structure. While 2 shows a one dimensional zigzag chain. Electrochemistry studies reveal that complex 2 undergo a quasi reversible one-electron metal-centered redox process at E _1/2 = +0.062 V.     

Synthesis and crystal structures of two copper(I) π-complexes with 1-allyloxybenzotriazole of CuBr?C6H4N3(OC3H5) and 2CuCl?C6H4N3(OC3H5) compositions

Both compounds of CuBr⋅C₆H₄N₃(OC₃H₅) (sp. gr. P1, a = 7.633(1) Å, b = 9.987(1) Å, c = 14.898(2) Å, α = 104.75(1)^∘, β = 94.76(1)^∘, γ = 106.90(1)^∘) (I) and 2CuCl⋅C₆H₄N₃(OC₃H₅) (sp. gr. Cc, a = 11.2483(4) Å, b = 16.7076(6) Å, c = 7.2948(3) Å, β = 118.612(2)^∘) (II) composition were prepared by alternating-current electrochemical synthesis. In I due to a bridging function of organic moieties 16-membered cycles appear which are combined into ribbons {Cu₂Br₂[(C₆H₄N₃(OC₃H₅)]₂}_n. Each of two crystallographically independent copper atom possesses a trigonal-pyramidal arrangement with different degree of tetrahedral distortion. Distinctive numbers of hydrogen bonds around Br1 and Br2 atoms cause rather appreciable distinctions in copper–olefinic bond interaction effectiveness for each metal atom. In II Cu₂Cl₂ rhombs are joined to infinite chains oriented along [010] direction. Each ligand molecule is also coordinated through the C=C—bond of the allylic group to copper atom of one inorganic chain and through the nitrogen atom to a metal atom belonging to another copper-halide chain. Cu1 atoms is tetrahedrally surrounded by three chlorine atoms and nitrogen one, whereas a trigonal-planar arrangement of Cu2 atom is formed by two halogen atoms and slightly disordered olefinic group.     

Crystal structure of bis[diethylenetriamine-N′-(3-propionato)-N, N′,N″,O,O′]dicopper(II) Diperchlorate, [Cu2(4-Dtmp)2](ClO4)2

A complex of copper(II) with the diethylenetriaminemonopripionate ligand [Cu₂(4-Dtmp)₂](ClO₄)₂ (I) is synthesized and characterized using X-ray diffraction. The crystals of compound I are monoclinic, a = 7.740(2) Å, b = 19.199(3) Å, c = 8.449(2) Å, β = 91.61(2)°, Z = 2, and space group P2₁/n. The structural units of crystal I are centrosymmetric dimeric cations and statistically disordered ClO ₄ ⁻ anions. In the cation, the copper atom is coordinated by three N atoms [mean Cu-N, 2.01(1) Å] and two O atoms [Cu-O, 2.134(6) Å and 1.958(7) Å] of the pentadentate bridging-chelate Dtmp ligand, which occupy vertices of the trigonal bipyramid. The binuclear cations are linked via centrosymmetric pairs of hydrogen bonds into ribbons aligned parallel to the a axis of the crystal. The ClO ₄ ⁻ anions form columns in the same direction. In the crystal, the cationic ribbons and anionic columns alternate in a chessboard fashion. __________ Translated from Kristallografiya, Vol. 50, No. 3, 2005, pp. 450–454. Original Russian Text Copyright ? 2005 by Antsyshkina, Sadikov, Poznyak, Sergienko.     

The isomorphous substitution of 2H+ for the Cu2+ cation in the complex of bis(aminoguanidine)copper(II): Crystal structures of (Cu0.61H0.78Agu2)B12H12 and (HAgu)2B12H12

An X-ray diffraction study of the (Cu_0.61H_0.78 Agu ₂)B₁₂H₁₂ (I) mixed crystal and one of its components (HAgu)₂B₁₂H₁₂ (II) is performed at 160 K (R = 0.0312 and 0.0345, respectively). Crystals I and II are isostructural. In I, two H⁺ ions partially substitute the Cu²⁺ cation, resulting in a combination of [CuAgu ₂]²⁺ and (HAgu ₂)₂₊ cations in the structure. The cations and polyhedral B₁₂H₁₂²⁻ anions have centrosymmetric structures. A square planar environment for the Cu atom is formed by four N atoms of two Agu molecules, which close five-membered chelate cycles [Cu-N, 1.9702(13) and 2.0261(10) ?]. The distant apical vertices are occupied by H atoms of the B₁₂H₁₂²⁻ anions [Cu…H, 2.805(14) ?]. In the dimeric (HAgu ₂)²⁺ cations, the proton that substitutes for the Cu²⁺ cation forms a three-center N(1)-H…N(4),N(4)′ hydrogen bond which consists of intramolecular and an intermolecular components. In crystal II, the N(1)…N(4) and N(1)…N(4)′ distances [2.685(1) and 3.111(1) ?] are longer than in I [2.610(2) and 3.027(2) ?]. In I, the Cu…H interactions connect [CuAgu ₂]²⁺ cations and B₁₂H₁₂²⁻ anions into chains. In the cells that contain the (HAgu ₂)²⁺ dimeric cation, the chains are retained due to the secondary N-H…(B-H) interactions. Numerous weak secondary interactions between the cations and anions form three-dimensional frameworks in structures I and II.     

Crystal structure of R[UO2(CH3COO)3] (R = NH 4+ , K+, or Cs+)

The single crystal structure of NH₄[UO₂(CH₃COO)₃] (I), K[UO₂(CH₃COO)₃] (II), and Cs[UO₂(CH₃COO)₃] (III) is studied by X-ray diffraction. I and II crystallize in the tetragonal crystal system. The crystal data are as follows: a = 13.6985(3) and c = 27.5678(14) ?, V = 5173.1(3) ?³, space group I4₁/a, Z = 16, and R = 0.023 for I; a = 13.8890(5) and c = 26.0839(18) ?, V = 5031.7(4) ?³, space group I4₁/a, Z = 16, and R = 0.037 for II. Crystals III are orthorhombic, a = 18.176(2), b = 13.119(2), and c = 22.088(4) ?, V = 5267(1)?³, space group Pbca, Z = 16, and R = 0.0424. In structures I–III, the uranium-containing structural units are represented by discrete mononuclear [UO₂(CH₃COO)₃]⁻ groups, which belong to the AB ₃⁰¹ (A = UO₂²⁺, B ⁰¹=CH₃COO⁻) crystal chemical group of uranyl complexes.     

Structures of mixed-ligand Manganese(II) compounds [Mn(Heida)(Phen)]2 · 7H2O and [Mn2(Edta)(Phen)] · 4H2O

The crystal structures of [Mn(Heida)(Phen)]₂ · 7H₂O (I) and [Mn₂(Edta)(Phen)] · 4H2O (II) are studied by X-ray diffraction [R ₁ = 0.0375 (0.0283) and wR ₂ = 0.0954 (0.0662) for 5449 (3176) observed reflections in I (II), respectively]. Structure I contains mononuclear mixed-ligand complexes [Mn(Heida)(Phen)] and [Mn(Heida)(Phen)(H₂O)]. In structure II, the [Mn(Edta)]²⁻ anionic complexes and the [Mn(Phen)(H₂O)₂]²⁺ cationic complexes are linked by the bridging carboxyl groups into the tetramers with C ₂ symmetry. In both compounds, two independent Mn atoms have different coordination numbers (6 and 7). __________ Translated from Kristallografiya, Vol. 47, No. 2, 2002, pp. 280–285. Original Russian Text Copyright ? 2002 by Polyakova, Sergienko, Poznyak.     

Crystal structure of the Lanthanum(III) complex [La(DMSO)6(H2O)PW12O40] · C2H5OH (DMSO is dimethyl sulfoxide)

The crystal structure of the [La(DMSO)₆(H₂O)PW₁₂O₄₀] · C₂H₅OH complex (I) (where DMSO is dimethyl sulfoxide) is determined by X-ray diffraction analysis. The coordination polyhedron of the La atom is a distorted tricapped trigonal prism in which two cap sites are occupied by oxygen atoms of the heteropolyanions. For these atoms, the La-O distances [2.760(9) and 2.801(9) Å] are considerably longer than the other distances [ranging from 2.441(10) to 2.569(10) Å] in the environment of the La atom. __________ Translated from Kristallografiya, Vol. 47, No. 6, 2002, pp. 1039–1041. Original Russian Text Copyright ? 2002 by Grigoriev, Shirokova, Fedoseev, Den Auwer.     

The structure of the scandium iodide complex with antipyrine (AP) and its comparison with the structure of nonisostructural analogues (Compounds [Ln(AP)6]I3 (Ln = La, Y, or Eu))

An X-ray diffraction study of the scandium iodide complex with antipyrine [Sc(AP)₆]I₃ (AP is antipyrine, i.e., 2,3-dimethyl-1-phenyl-3-pyrazolin-5-one) (I), which is not isostructural to the analogous compounds of Y, La, and Eu (II), is performed. Crystals I are trigonal; a = 24.911 ? and c = 10.140 ?; Z = 3, space group P $ \bar 3 $ \bar 3 . Crystal I is built of [Sc(AP)₆]³⁺ complex cations of two types and I⁻ anions. In both cations, the Sc atom is octahedrally coordinated by six O atoms of six AP ligands (Sc-O, 2.054–2.078 ?). Complexes I differ from II by the absence of π-π stacking interactions between AP molecules, resulting in a supramolecular cation. Complex cations I of both types form combined layers. All I⁻ anions are located in the interlayer space, being statistically disordered within a flat area limited by eight complex cations of Sc1 and Sc2.     

Crystal structure of M4[(UO2)2C2O4(SO4)2(NCS)2] ( M = K+, Rh+) and K4[(UO2)2C2O4(SeO4)2(NCS)2]

Three heteroacidoligand uranyl complexes M ₄[(UO₂)₂C₂O₄(SO₄)₂(NCS)₂] (M = K⁺ (I), Rb⁺ (II)) and K₄[(UO₂)₂C₂O₄(SeO₄)₂(NCS)₂] (III) have been synthesized and their crystal structure has been determined by X-ray diffraction analysis. The compounds I–III are isostructural and crystallized in the monoclinic system, sp. gr. P2₁/c, Z = 2, a = 11.5548(3) ?, b = 7.0847(1) ?, c = 13.5172(3) ?, β = 93.130(1)°, V = 1104.90(4), R = 0.015 (I); a = 11.5854(9) ?, b = 7.3841(6) ?, c = 13.9072(9) ?, β = 95.754(3)°, V = 1183.74(15), R = 0.0235 (II); a = 11.6715(3) ?, b = 7.1418(2) ?, c = 13.8546(1) ?, β = 93.539(1)°, V = 1152.66(5), R = 0.0126 (III). Basic structural units of these crystals are [(UO₂)₂C₂O₄(XO₄)₂(NCS)₂]⁴⁻ chains, which belong to the crystallochemical group A ₂ K ⁰² B ₂² M ₂¹ (A = UO₂²⁺, K ⁰² = C₂O₂₋⁴, B ² = SO₄²⁻ or SeO₄²⁻, M ¹ = NCS⁻) of uranyl complexes. Uranium-containing chains are connected into a 3D framework via a system of electrostatic interactions with potassium or rubidium cations from outer spheres. Original Russian Text ? I.V. Medrish, E.V. Peresypkina, A.V. Virovets, L.B. Serezhkina, 2008, published in Kristallografiya, 2008, Vol. 53, No. 3, pp. 495–498.     

Palladium (II) compounds with diaminocarboxylic acids: Crystal structures of [Pd(H2Cdta)] · H2O, [Pd(H3Edtp)Cl] · 2H2O, and (H6Edtp)[PdCl4] · 4H2O

The crystal structures of three Pd(II) compounds with diamine tetracarboxylates in different protonation states are determined, namely, [Pd(H₂ Cdta)] · H₂O (I), [Pd(H₃ EdtpCl] · 2H₂O (II), and (H₆ Edtp)[PdCl₄] · 4H₂O (III) (R ₁ = 0.0230, 0.0313, and 0.0277 for 3040, 3377, and 3809 reflections with I > 2σ(I) for I–III, respectively). Crystals I and II are built of neutral complexes [Pd(H₂ Cdta)] and [Pd(H₃ Edtp)Cl], respectively, and crystallization water molecules. Crystal III consists of [PdCl₄]²⁻ anionic complexes, H₆ Edtp ²⁺ cations, and water molecules. In I, one of the protonated acetate groups of the H₂ Cdta ²⁻ ligand forms a very weak additional Pd-O bond [2.968(2) Å] over the 2N + 2O coordination square. In II and III, the protonated propionate groups of the H₃ Edtp ⁻ ligand and the H₆ Edtp ²⁺ cation are not involved in Pd coordination and the coordination squares consist of the 2N + O + Cl and 4Cl atoms, respectively. __________ Translated from Kristallografiya, Vol. 48, No. 2, 2003, pp. 278–282. Original Russian Text Copyright ? 2003 by Polyakova, Poznyak, Sergienko.     

Solvothermal Syntheses and Crystal Structures of Neodymium Thiostannates [Nd(dien)3]2[(Sn2S6)Cl2] and [Nd(dien)3]2[(Sn2S6)(SH)2]

Abstract  

Two neodymium thiostannates [Nd(dien)₃]₂[(Sn₂S₆)Cl₂] (1) and [Nd(dien)₃]₂[(Sn₂S₆)(SH)₂] (2) (dien = diethylenetriamine) were synthesized by the reaction of tin and sulfur in the presence of NdCl₃ and Nd₂O₃, respectively under solvothermal conditions. Compounds 1 and 2 crystallize in monoclinic space group P2₁/n. Crystallographic data for 1: a = 11.6722(16), b = 15.119(2), c = 14.1566(19) ?, β = 96.213(3)°, V = 2483.6(6) ?³, Z = 4. For 2: a = 11.7190(14), b = 15.2168(19), c = 14.2209(18) ?, β = 95.775(4)°, V = 2523.1(5) ?³, Z = 4. The nine-coordinate [Nd(trien)₃]³⁺ complex cation formed in situ acts as the counter ion to the [Sn₂S₆]⁴⁻ anion. The [Nd(dien)₃]³⁺, [Sn₂S₆]⁴⁻ and Cl^– (or SH^–) ions form a 3-dimensional network structure through the N–H···S and N–H···Cl hydrogen bonds.     

Synthesis, characterization and crystal structure of [Ni(DACH)2](H2O)2(CH3COO)2 (DACH = 1,4-diazacycloheptane): a three-dimensional (3-D) hydrogen-bonded network embodying 1-D water chains

The mononuclear complex [Ni(DACH)₂](H₂O)₂(CH₃COO)₂ (DACH = 1,4-diazacyclo-heptane) has been synthesized and characterized by IR, UV-Vis, elemental analysis and single crystal X-ray diffraction. The complex crystallizes in monoclinic system, P2₁/n space group with a=7.500(3) ?, b=8.788(3) ?, c=16.429(6) ?, β=93.395(5)°, D _c =1.269 g cm⁻³, μ=0.930 mm⁻¹, V=1080.9(6) ?³, Z=2. The central Ni^II atom is in a square-planar coordination geometry formed by four N atoms of two DACH chelated ligands. The notable feature of the title compound resides in the formation of a three-dimensional network through hydrogen bonds between the [Ni(DACH)₂]²⁺ cations, the CH₃COO⁻ counter anions and the guest water molecules trapped in the crystal lattice.     

Reactions of triosmium clusters with indole: X-ray structures of [Os3(CO)10(μ-OH)(μ-OMeCO)] and [Os3(μ-H)(CO)10(μ-1, 2-η2-NC8H6)]

Treatment of [Os₃(CO)₁₂] with indole in presence of a methanolic solution of Me₃NO⋅2H₂O at 60^∘C afforded the previously reported compounds [(μ-H)Os₃(CO)₁₀(μ-OMe)] 2, [(μ-H)Os₃(CO)₁₀(μ-OH)] 3 and [Os₃(CO)₁₀(μ-OH)(μ-OMeCO)] 4 in 10, 5 and 20% yields, respectively. The reaction of [Os₃(CO)₁₀(MeCN)₂] with indole at room temperature gave [(μ-H)Os₃(CO)₁₀(μ-1,2-η²-NC₈H₆)] 5 in 40% yield. Compounds 4 and 5 have been characterized by single crystal X-ray diffraction studies. Compound 4 crystallizes in the monoclinic space group P2(1)/c with a = 23.1239(3), b = 9.8087(4), c = 16.9017(6) ?, β = 92.6998(14)^∘, Z = 8 and V = 3829.3(2) ?³ and 5 crystallizes in the monoclinic space group P2(1)/c with a = 9.009(3), b = 9.764(4), c = 24.906(6) ?, β = 93.452(14)^∘, Z = 4 and V = 2186.9(13) ?³. Compound 4 consists of an open cluster of three osmium atoms with the hydroxy and methoxycarbonyl ligands bridging the open Os–Os edge. Compound 5 consists of an isosceles triangle of osmium atoms with one elongated Os–Os edge which is bridged by the hydride and the indolyl ligands.     

Crystal Structure of [Co(NH3)5NO3](NO3)(PF6)?·?1.5H2O and the Vibrational Bands of its Normal and 15NO3-Enriched Cation

The crystal structure of [Co(NH₃)₅NO₃](NO₃)(PF₆) ·1.5 H₂O was studied by X-ray diffraction methods in order to obtain the unknown molecular structure of the [Co(NH₃)₅NO₃]²⁺ cation . The substance crystallizes in the monoclinic system, space group C2/m, with a = 18.6231(6) ?, b = 7.8757(3) ?, c = 9.6434(3) ? and β = 95.484(2)°. An infrared and Raman study of the bromide salt was also performed and the spectra interpreted with the aid of ¹⁴NO₃/¹⁵NO₃ isotopic replacement and quantum chemistry calculations. E.L. Varetti — Member of the Carrera del Investigador Científico, CONICET, R. Argentina