Structural and Physical Characterization of 1:1 9,9′-Bifluorenylidene Complex with 7,7,8,8-Tetracyanoquinodimethane,BFL-TCNQ

The crystal and molecular structure of BFL-TCNQ has been determined by single-crystal X-ray diffraction analysis. The complex crystallizes in the monoclinic space group C2/c, a=17.915(3), b=12.238(3), c=13.531(3) Å, β = 115.16(1)°, and Z=4. The complex has a mixed-stacked crystal structure in which BFL molecules exist in a twisted conformation and TCNQ molecules are dimensionally similar to uncomplexed TCNQ. The complex is diamagnetic and is an insulator with a room-temperature conductivity less than 10⁻⁹ s cm⁻¹. The FT-IR spectrum of the BFL-TCNQ complex reveals that the degree of charge transfer between the two component molecules is essentially null.     

Acyl- und Alkylidenphosphane. XXXII [1, 2]. Di-cyclo-hexoyl- und Diadamant-1-oylphosphan — Keto-Enol-Tautomerie und Struktur

Acyl- and Alkylidenephosphines. XXXII. Di-cyclohexoyl- and Diadamant-1-oylphosphine – Keto-Enol Tautomerism and Structure Lithium dihydrogenphosphide · DME (¹) [12] and cyclo-hexoyl or adamant-1-oyl chloride react in a molar ratio of 3:2 to give lithium di-cyclo-hexoylphosphide · DME and the corresponding diadamant-1-oylphosphide.2THF (¹) resp. Treatment of these two compounds with 85% tetrafluoroboric acid. diethylether adduct yields di-cyclo-hexoyl- ( 1b ) and diadamant-1-oylphosphine ( 1c ). In nmr spectroscopic studies 1b over a range of 203 to 343 K, a strong temperature dependence of the keto-enol equilibrium is found; thermodynamic data characteristic for the formation of the enol tautomer (ΔH⁰ = ?4.3 kJ. mol^?1; ΔS⁰ = ?9.2 J. mol^?1. K (^?1) are compared of 1,3-diketones. The enol tautomer of diadamant-1-oylphosphine ( E-1c ) as obtained from a benzene solution in thin colourless plates, crystallizes in the monoclinic space group P2₁/c {a = 722.2(2); b = 1085.5(4); c = 2434.8(5) pm; ß = 96.43(2)° at –100 ± 3°C; Z = 4}. An X- ray structure analysis (R_w = 0.033) shows bond lengths and angles to be almost identical within the enolic system (P? C 179/180; C? O 130/129; C? C(adamant-1-yl) 152/153 pm; C? P? C 99°; P? C? O 124°/124°; P? C? C 120°/120°; C? C? O 116°/116°. The geometry of the very strong, but probably asymmetric O‥H‥O bridge is discussed (O? H 120/130, O‥O 245 pm).     

Transition-metal complexes with bidentate ligands spanning trans-position. Part XVI. X-ray structural and 31P-NMR solution studies of 2,11-Bis(diethylphosphinomethyl)benzo[c]phenanthrenesilver(I) perchlorate

The preparation of complexes {AgX(1c)} (X ? Cl, Br, I, NO₃ and ClO₄; 1c = 2,11-bis(diethylphosphinomethyl)benzo[c]phenanthrene) is reported. The ³¹P-NMR spectra of the above complexes were recorded and the ¹J(¹⁰⁷Ag, ³¹P) values are compared with the corresponding data for related complexes. The X-ray crystal structure of [Ag(1c)](ClO₄) was determined. There are two crystallographically independent molecules in the unit cell each containing two-coordinate silver, the O-atoms of the perchlorate anions being outside bonding range from the central atom. The two molecules, however, show different bonding parameters: Thus for ‘molecule 1’ P(1)? Ag(1)? P(2) = 167.6(1)°, Ag(1)? P(1) = 2.389(3) and Ag(1)? P(2) = 2.393(3) Å, while for ‘molecule 2’ P(3)? Ag(2)? P(4) = 164.8(1)°, Ag(2)? P(3) = 2.377(3), and Ag(2)? P(4) = 2.378(3) Å. These differences are probably due to packing forces in the crystal lattice.     

Synthesis, 13C NMR spectrum and crystal structure of 10-Phenylpyrido[3,2-b][1,4]benzothiazine 5-Oxide

The compound 10-phenylpyrido[3,2-b][1,4]benzothiazine 5-oxide, 1 , has been obtained in nearly quantitative yield oxidation of 10-phenylpyrido[3,2-b][1,4]benzothiazine with oxygen in dioxane solution. The ¹³C nmr chemical shift assignments of 1 are reported. Its structure has been determined by X-ray single crystal methods. The crystals of 1 are monoclinic, space group P2₁/n. There are four molecules in a unit-cell of dimensions a = 12.347(3), b = 12.947(3), c = 8.987(1)Å, β = 106.73(1)° and V = 1375.8(5) ų. The central ring is in a boat conformation and the sulfoxide oxygen atom occupies the axial position. The folding angle between the planes of the pyrido and the benzo planes is 161.55(9)°.     

Crystal and molecular structure of the ethanol solvate of 2-[bis(diphenylphosphoryl)methyl]phenol

Crystal and molecular structure of the ethanol solvate of 2-[bis(diphenylphosphoryl)methyl]phenol, C₃₁H₂₆O₃P₂·3/4 C₂H₅OH (I), was determined by X-ray diffraction analysis. Crystals I are monoclinic: a=11.896(3), b=17.207(3), c=28.421(6) Å, β=90.75(2)°, Z=8, space group P2₁/c. The structure of I was solved by direct methods and refined anisotropically by large-block least-squares analysis to R=0.066 (CAD-4 automatic diffractometer, λMoK_α radiation, 3650 independent reflections with I≥3σ). The crystal structure of I contains two independent molecules, Ia and Ib, of the basic substance and two independent solvate molecules of ethanol. The P atoms in molecules Ia and Ib have distorted tetrahedral environments; the average bond lengths are: P=O 1.476(3), P-C(sp³)=1.833(4) and P-C(Ar)=1.809(4) Å. Molecule Ia has an approximate symmetry plane C_s. The conformation of molecule Ib differs from that of Ia in rotation of one diphenylphosphoryl substituent around the P-C(sp³) bond by an angle of ≈34°. In molecule Ia, the O=P-C-P=O fragment has the form of a chela with two nearly parallel P=O bonds. In the crystal structure of I there are O-H...O=P intermolecular H-bonds; in molecules Ia and Ib there is an intramolecular H-bond of C-H...OH type.     

The crystal and molecular Structure of Trans-MoCl3(C5H5N)3

Trans-MoCl₃Py₃ (Py 7mdash; pyridine) crystallizes in the monoclinic space group P2₁/c with four molecules in the unit cell. The cell dimensions are: a = 9.229(3), b = 12.555(3), c = 17.920(4) Å and β = 119.33(2)°. Calculated density for Z = 4 is 1.61 gcm^?3 and measured 1.61 ± 0.02 gcm^?3. Structure has been solved from 1594 independent film data and refined to the conventional R factor 9.1%. Three chlorine atoms and three nitrogen atoms of the pyridine molecules form an octahedral coordination about molybdenum in the 1, 2,6 or trans configuration. Distances within octahedron are: Mo? Cl 2.437(5), 2.424(5), 2.423(5) Å, and Mo? N(pyridine) 2.189(13), 2.163(15), 2.223(15) Å. CrCl₃Py₃, CrBr₃Py₃ and MoBr₃Py₃ crystallize in the same space group with comparable cell dimensions and are probably isostructural with trans-MoCl₃Py₃.     

Crystal Structure of 1,3,4,6-Tetra-O-Acetyl-2-deoxy-2-fluoro-β-D-Galactopyranoside

Abstract

1, 3, 4, 6-Tetra-O-acetyl-2-deoxy-2-fluoro-β-D-galactopyranoside is a key intermediate in the synthesis of phenyl-2-fluoro-2-deoxy-α-D-galactopyranoside which is used in the studies of the inhibitoty activities of α-2-L-fucosyl transferase. Crystals of the title compound (C₁₄H₁₉0₉F) are triclinic, space group P1, with cell dimensions a=7.679(1), b=9.933(1), c=11.458(2)A⁰, α=89.31(1), β=72.83(1), γ=86.49(1)°, V=833.5å³, Z=2 (two independent molecules in the unit cell), F.W. 351.3, D_obs = 1.39 g/c.c, D_calc = 1.401 g/c.c, CAD-4 diffractometer data (3533 reflections, 2483 > 3ρ) and final R = 0.048. The sugars of both the independent molecules have chair conformations with C(3) and 0(1) deviating by 0.64 and-0.66Å in one molecule and C(2) and C(5) deviating by 0.70 and-0.69Å in the other molecule from the best plane involving the other four atoms of the pyranose ring. The conformation across C(5)-C(6) is gauche-trans in both molecules. The acetyl groups take up the preferred trans conformation across the C-O bond.     

Synthesis and Crystal Structures of Nickel(II) and Copper(II) Complexes of Meso-3,6,6,9-Tetramethyl-4,8-Diazaundecane-2,10-Dione Dioxime

The nickel(II) and copper(II) complexes of meso-3,6,6,9-tetramethyl-4,8-diazaundecane-2,10-dione dioxime (meso-HM-PAO) have an intramolecular hydrogen bond between cis oxime groups. [Cu(meso-HM-PAO-H)(H₂O)](NCS) crystallizes in space group P2₁/n with a = 7.692(1), b = 12.028(2), c=20.235(3) Å, β=93.03(1)°, Z = 4 and Dc=1.46 g/cm³. The final R value for this complex was 0.034 for 2223 observed reflections with I ≥ 2.5σ (I). The Cu(II) coordination is a distorted square pyramid. The Cu(II) ion is five-coorinated with the diazadioxime N atoms equatorial and water O atom axial. The Cu(II) is 0.12 Å from the equatorial plane towards the hydrate. The equatorial Cu-N distances span a narrow range, 1.953(3)-1.999(3) Å. The axial Cu-O distance is 2.314(3) Å. The thiocyanate group is almost linear. The intramolecular O ?O hydrogen bond length is 2.479(4) Å. [Ni(meso-HM-PAO-H)](ClO₄) crystallizes in space group P2₁/c with a = 14.774(3), b = 12.752(3), c = 20.035(4) Å, β = 92.94(3)°, Z = 8 and Dc = 1.51 g/cm³. The final R value for the complex was 0.053 for 4794 observed reflections with F ≥ 4σ (F). The coordination about Ni(II) is a slightly distorted square plane. The Ni(II) ion is 0.0673(7) Å from the best plane of the four donor nitrogen atoms away from the perchlorate ion. The Ni-N distances span a narrow range 1.863(4)-1.927(4) Å. There are two molecules per asymmetrical unit resulting in eight molecules being packed in an unit cell; they are bound together by van der Waals interactions. The O-H ?O bonds of these complexes give characteristic infrared absorptions as well as chemical shift of the ¹H NMR signal (Ni complex).     

Molecular and crystal structure of 1-amino-3,5-diphenyl-2,4,4,6,6-Pentacyano-cyclohex-1-ene and 1-amino-3,5-diphenyl-2,4,4,6-tetracyanocyclohex-1-ene

Molecular and crystal structures of 1-amino-3,5-diphenyl-2,4,4,6,6-pentacyano-cyclohex-1-ene (I) and 1-amino-3,5-diphenyl-2,4,4,6-tetracyanocyclohex-1-ene (II) are studied to examine intermolecular interactions. Crystal data for (I): space group P2₁, a=11.172(3), b=6.561(2), c=16.390(4) Å, β=100.25(2)⁰, V=1182.1 ų, Z=2, R=0.046; for (II): space group P1, a=10.756(3), b=10.890(3), c=12.999(3) Å, α=62.20(2), β=70.73(2), γ=65.42(2)⁰, V=1207.2 ų, Z=2, R=0.074. Intermolecular bonds via the aminonitrile fragment in (I) lead to formation of chains along they axis: N1…N6′ (1?x, ?1/2+y, 1?z) of 3.465(8) Å, N6…N1″ (1?x, 1/2+y, 1?z), and the contact with the solvent (acetone) O1…N1 of 2.984(7) Å. In compound (II), the intermolecular contacts N1…N5′ (?x+1, ?y, ?z+1) of 3.064(7) Å link the molecules into dimeric associates.     

Zwitterionic Melaminium Trichloromercurate(II), [MelH+HgCl3‐](Mel)

Colourless long and thin needles of the reaction product of melamine with mercuric chloride in water/methanol, [MelH⁺HgCl₃^‐](Mel), crystallize with a structure that contains zwitterionic molecules [MelH⁺HgCl₃^‐] and “free” melamine (Mel) molecules; monoclinic, P2₁, Z = 2, a = 939.43(18), b = 682.80(9), c = 1218.9(2) pm, β = 99.61(2)°, R(all) = 0.0291, T = 20 °C.     

Bildung und Eigenschaften von Aoylphosphinen. III. Molekül- und KristallStruktur von Dipivaloylphosphin

Syntheses and Properties of Acylphosphines. III. Molecular and Crystal Structure of Dipivaloylphosphine In the reaction of tris(trimethylsilyl)phosphine with pivaloyl chloride two Si? P bonds are cleaved and dipivaloyltrimethylsilylphosphine is formed. Reaction with methanol yields dipivaloylphosphine. N.m.r. investigations show a tautomeric equilibrium between keto and enol form as in β-diketones. The substance crystallizes in the orthorhombic space group Pmmn with molecules in two crystallographically different sites [cell parameters: a = 14.04(1), b = 13.82(1), c = 6.28(2) Å]. An X-ray structure determination (R = 5.0%) proves the existence of the enol form in the solid, in that (1.) the molecular symmetry is mm 2(C_2v), (2.) P? C bonds are shortened and C? O bonds are elongated, and (3.) we find a symmetric hydrogen bridge with a very short O? O distance. Bond lengths and angles are compared with those of other β-diketones. The packing of molecules is studied in detail.     

Crystal structure of platinum(II) chloro(1,1,1-trifluoro-4-imino-2-pentanononate(Hydrate)) [PtCl(ktf)H2O]

This paper reports on our study of the mixedligand βiminoketonate complex [PtCl(ktf)H₂O] including 1,1,1-trifluoro-4-imino-2-pentanone as a ligand. An X-ray diffraction analysis was performed on a CAD-4 diffractometer (MoK_α radiation, ω/2θ scan mode). Crystal data ofPtClF₃O₂NC₅H₇: a = 26.264(5), b = 4.750(1), c = 15.955(3) Å, β = 108.16(3)°, V = 1891.3ų, space group C2/c, Z = 8, d_calc = 2.82 g/cm³. The Pt atom has a distorted square planar environment. The Pt-Cl, Pt-O(H₂O), Pt-N, and Pt-O bonds are 2.29, 2.07, 1.97, and 1.98 Å in length, respectively. The chelate angle is 93.7°. The environment of Pt is completed to pyramidal due to interactions with the C_γ atom of the neighboring molecule at a distance of 3.57 Å. The compound has a molecular structure. The molecules of the complex are stacked along the Y direction.     

Synthesis and crystal structure of Na2[RuNOCl5] · 6H2O

A procedure for the synthesis of Na₂[RuNOCl₅]·6H₂O is described. The complex was studied by IR spectroscopy and by thermal, X-ray phase, and X-ray diffraction analyses. Crystal data: a = 26.740(7), b = 31.581(7), c= 6.918(3) Å, V = 5842(3) ų space group Fdd2. Z = 16, d_calc= 2.103, d_exp = 2.112 g/cm³. The structure consists of [RuNOCl₅]^2? complex cations, Na⁺ cations, and crystallization water molecules. The compound is stable in conditions of high humidity of atmosphere but irreversibly loses up to four water molecules when stored in dry atmosphere. Removal of two water molecules is accompanied by crystal decay and changes in the crystal structure. Heating the substance above 100°C leads to a hygroscopic anhydrous complex Na₂[RuNOCl₅], which is stable below t = 375°C.     

Kristallstrukturen und thermisches Verhalten von Metalldihydrogenphosphat‐HF‐Addukten MH2PO4 · HF (M = K,Rb, Cs) mit Wasserstoffbrückenbindungen vom Typ F–H…O

Structures and Thermal Behaviour of Alkali Metal Dihydrogen Phosphate HF Adducts, MH₂PO₄ · HF (M = K, Rb, Cs), with Hydrogen Bonds of the F–H…O Type Three HF adducts of alkali metal dihydrogen phosphates, MH₂PO₄ · HF (M = K, Rb, Cs), have been isolated from fluoroacidic solutions of MH₂PO₄. KH₂PO₄ · HF crystallizes monoclinic: P2₁/c, a = 6,459(2), b = 7,572(2), c = 9,457(3) Å, β = 101,35(3)°, V = 453,5(3) ų, Z = 4. RbH₂PO₄ · HF and CsH₂PO₄ · HF are orthorhombic: Pna2₁, a = 9,055(3), b = 4,635(2), c = 11,908(4) Å, V = 499,8(3) ų, Z = 4, and Pbca, a = 7,859(3), b = 9,519(4), c = 14,744(5) Å, V = 1102,5(7) ų, Z = 8, respectively. The crystal structures of MH₂PO₄ · HF contain M⁺ cations, H₂PO₄^– anions and neutral HF molecules. The H₂PO₄^– anions are connected to layers by O–H…O hydrogen bonds (2,53–2,63 Å), whereas the HF molecules are attached to the layers via very short hydrogen bonds of the F‐H…O type (2,36–2,38 Å). The thermal decomposition of the adducts proceeds in three steps. The first step corresponds to the release of mainly HF and a smaller quantity of water. In the second and third steps, water evolution caused by condensation of dihydrogen phosphate is the dominating process whereas smaller amounts of HF are also released.     

Molecular and crystal structure of pyrylium squarylium dyes

The crystal structures of new dyes: 4-[[3-[[2,6-bis-(tert-butyl)-4H-pyran-4-ylidene]methyl]-2-oxido-4-oxo2-cyclobuten-]-ylidene]methyl]2,6-bis(tert-butyl)pyrylium (I) and its thio analog (II) were determined. Crystal data: space group P1 (I), P2₁/n (II); a = 5.960(9) Å (I), 10.400(4) Å (II); b = 9.366(3) Å (I), 12.242(4) Å (II); c = 13.948(3) Å (I), 14.482(6) Å (II); α = 70.43(2)° (I), 90.0° (II); ß = 84.82(9)° (I), 94.65(3)° (II); γ = 79.10(9)° (I), 90.0° (II); V = 720.0 ų (I), 1837.7 ų (II); Z = I (I), 2 (II); d_calc = 1.131 g/cm³ (I), 086 g/cm³ (II); R1(F) 0.049 (I), 0.045 (II). The substituents are trans-oriented relative to the planar 4-membered ring. Bond length distribution points to a considerable electron density delocalization over the whole molecule except the Bu^t groups. The pyrane rings are oriented differently relative to the central group; in II the rings lie in the same plane which is rotated through 7.7° with respect to the central fragment, whereas in I they lie in parallel planes which are 1.38 Å apart and deviate from the central fragment to opposite sides, forming with it dihedral angles of 12.8°. These conformational differences are possibly the result of the action of crystal field forces. In I molecules are arranged as overlapping stacks, whereas in II the pairwise parallel dye molecules are oriented in such a way that their long molecular axes are perpendicular to the long axes of the neighboring pair, resulting in a herringbone packing.     

Structural study of 5-methoxyfuro[3,2-e]imidazo[1,2-c]pyrimidine

The nmr and X-ray diffraction data of the novel ring system furo[3,2-e]imidazo[1,2-c]pyrimidine are reported in this paper. The crystal and molecular structure of this compound (C₉H₇N₃O₂·1/2H₂O) has been solved at room temperature. Crystals are monoclinic in a space group of P2/n with cell constants a = 9.982(8), b = 13.526(9) and c = 13.981(9) Å, β = 107.44(5)°, V = 1800.9 ų, Z = 8, D_x = 1.462 Mg·m^?3. The structure was solved by full matrix least square refinement giving a final R = 0.054 (Rw = 0.069) for 1263 reflections (I>3.0σ(I)). The compound is essentially planar, existing in two slightly structural different forms, A and B. These are held in pairs with symmetry related molecules by hydrogen bonds formed with two water molecules. Then the dimeric units are stacked parallel to the c axis to form the tridimensional packing.     

Molecular and crystal structure of Bis(η5-cyclopentadienyl)titanium(IV) Dibromide,Ti(η5-C5H5)2Br2

The crystal and molecular structure of Bis(η⁵-cyclopentadienyl)titanium(IV) dibromide, Ti(η⁵?C₅H₅)₂Br₂, has been investigated by an X-ray structure determination. Crystal data: triclinic, a = 7.872(5), b = 11.807(5), c = 12.310(3) Å, α = 107.62(3), β = 100.83(4), γ = 90.69(4)°, V = 1 068(14) ų, T = 293, space group P1 , Z = 4 (there are two crystallographically independent molecules in the asymmetric unit cell and their conformations are similar). Final R and R_w values are 0.068 and 0.073, respectively. The structural results are compared to those for similar type molecules.     

Supramolecular Assembly of Functionalized Metalloporphyrins. Porous Crystalline Networks of Zinc-Tetra(4-Carboxyphenyl)Porphyrin

Abstract

Two crystalline compounds based on the Zn-tetra (4-carboxyphenyl)porphyrin building block have been prepared and structurally analysed by x-ray diffraction in order to ellucidate the characteristic supramolecular aggregation modes of this functionalized metalloporphyrin moiety. Crystals of the 1:1 complex with sec-phenethyl alcohol (1) are monoclinic, space group I2/a (No. 15), a = 14.420(1), b = 24.678(2), c = 33.688(2) Å, β = 90.03(2)°, D_c = 1.082 g/cm³, Z = 8, R = 0.080 for 3053 data. Those of the 1:3 complex with dimethylsulphoxide (2) are monoclinic, space group P2₁/n (No. 14), a = 14.881(1), b = 8.986(2), c = 37.550(3) Å, β = 94.21(1)°, D_c = 1.444 g/cm³, Z = 4, R = 0.093 for 4200 data. The two compounds consist of nearly square-pyramidal five-coordinate metalloporphyrin species, molecules of the sec-phenethyl alcohol (in 1) and dimethylsulphoxide (in 2) linking to the metal center at the axial site. In 2, two additional molecules of dimethylsulphoxide associate through H-bonds to the terminal carboxylic substituents of the porphyrin framework. Incorporation of the carboxylic functionality into the tetraarylporphyrin unit leads to the formation of hollow hydrogen-bonded lattices in both crystals. Uniquely structured two-dimensional networks of the porphyrin building blocks with very large cavities (approximately 16 × 21 Å) are formed in 1. These networks mutually interpenetrate each other in order to fill the empty voids, yielding a spectacular ‘concatenated’ arrangement.

One-dimensional polymeric patterns with smaller cavities (6.5 × 10 Å) are built in 2 by the interacting molecular components. In the condensed crystalline environment each such cavity is occupied by two dimethylsulphoxide molecules of adjacent chains. This study is part of an ongoing evaluation of the utility of functionalized metalloporphyrin building blocks in the designed construction of hollow lattices (with varying degree of rigidity and pore size) in molecular based solids. Correlation of current results to previous findings is also discussed.     

Crystal and molecular structure of the mixed-ligand complex Zn[S2CN(CH3)2]2Phen

The crystal and molecular structure of the mixed-ligand complex Zn[S₂CN(CH₃)₂]₂Phen is determined by single crystal X-ray diffractometry (CAD-4 diffractometer, MoK_α radiation, 3347 F(hkl), R = 0.0385). The crystals are monoclinic, a =13.340(3), b =13.827(3), c =24.698(5) å, Β =102.58(3)? V = 4446(2) å ³, Z = 8, d_calc = 1.452 g/cm³ , space group C2/c. The structure consists of monomeric molecules in which the zinc atom has a distorted octahedral environment (4S+2N). The molecular packing in the crystal involves dimers related by the 2 rotation axis and forming continuous chains along the c axis.     

X-ray diffraction study of the clathrate [MnPy4(NO3)2)]·2Py and complex [MnPy3(NO3)2] formed in the pyridine (Py)-manganese nitrate system

A clathrate compound [MnPy₄(NO₃)₂]·2Py was synthesized and studied by single-crystal X-ray diffraction analysis (KM-4 diffractometer, CuK_α,ω/2? scan mode,? _max=78°). The unit cell is base-centered orthorhombic, space group Ccca, a=12.097(4), b=15.197(4), c=17.213(4) Å, V=3164(2) ų, Z=4, R=0.072, for 632 reflections and 107 parameters in the least-squares analysis. The host molecule has 222 symmetry. Two monodentate nitrato groups and four pyridine ligands are coordinated to Mn(II) along the symmetry axes (the former via O). The pyridine guest molecules lie in the cavities of the crystal framework. For [MnPy₃(NO₃)₂)], only unit cell parameters were determined: a=12.467(5), b=9.514(2), c=16.383(5) Å,β=108.93(4), V=1838(1) ų space group C2/c or Cc (according to extinctions). The pyridine-manganese nitrate system is shown to be analogous to the previously investigated Co, Ni, Cu, Zn, and Cd systems.