Slow Evaporation Of Methanol Solution Research Articles

Synthesis and Study of the Crystal Structure of 2-[(Dipyrrolidin-1-yl) methylene] malononitrile

This study aims to synthesis 2-[(dipyrrolidin-1-yl)methylene] malononitrile 2 and identify its crystal structure by X-ray diffraction analysis. 2-[(dipyrrolidin-1-yl)methylene] malononitrile was prepared by a direct displacement of the methylthio group (SMe) in the 2-[bis(methylthio)methylene] malononitrile 1 with pyrrolidine as cyclic secondary amine by conjugating addition-elimination reaction under reflux conditions for two hours. The compound was obtained in high yield (80%). The structure of compound 2-[(dipyrrolidin-1-yl)methylene] malononitrile2 was identified by performing X-ray diffraction analysis. Suitable crystals of compound 2 were grown by slow evaporation of methanol solution of the compound. The compound 2 crystallized in an orthorhombic crystal system with a space group of Pbcn. In the title compound, the two cyanide groups and the two pyrrolidine rings adopted trans configurations across the C2=C3 bond. The bond lengths and angles of the two pyrrolidinyl rings in the compound are within the normal range. The maximum deviation of N5/C2/C3/C4/N5a/C4a is 0.002(1) around C4, and no deviation has been recorded for the fragment N1/N1a/C2/C3 (0.000 (1)°). The dihedral angle between the pyrrolidine ring and N1/N1a/C2/C3 is 33.06(8)°, and the dihedral angle between the pyrrolidine ring and N5/C2/C3/C4/N5a/C4a is 50.57(7)°. The crystal packing is stabilized by two intermolecular and one intramolecular C---H…N hydrogen bonds, which form a one-dimensional polymeric chain along the axis.

Syntheses, Characterization, and X-ray Crystal Structure of Binuclear Lanthanide Complexes Assembled with Schiff Base and Acetate

Herein we reported the binuclear complexes of the 1-(pyridin-2-yl)-2-(pyridin-2-ylmethylene)hydrazine ligand (HL) [Ln2(HL)2(CH3COO)6].n(H2O) (Ln = Y, Pr, Gd and Er). The binuclear complexes are characterized by IR and physical measurement. Spectroscopic evidence indicated that the Schiff base HL behave an N3 coordination tridentate ligand. The complexes are formulated as [{Ln(1-(pyridin-2-ylmethylidene-kN)-2-(pyridin-2-yl-kN)hydrazine-kN1)(h2-OOCH3)2}{h1:h2:m2-OOCH3}2{Ln(1-(pyridin-2-ylmethylidene-kN)-2-(pyridin-2-yl-kN)hydrazine-kN1))(h2-OOCH3)2}].n(H2O). The structure of the praseodymium complex was elucidated by X-ray diffraction analysis. Suitable crystals were grown by slow evaporation of methanol solution. The asymmetric unit of the compound contains two neutral ligand molecules, two Pr3+ ions, four acetate anions acting in h2-OOCH3 mode, two acetate anions acting in h1:h2:m2-OOCH3 mode, and three uncoordinated water molecules. The praseodymium atom is ten coordinated and the coordination sphere is best described as a distorted bicapped square antiprism. The PrIII···PrIII distance is 4.2777(6) Å and the bridging angle Pr—O—Pr and O—Pr—O are respectively 115.8(3)° and 64.2(3)°. The structure is consolidated by intra and intermolecular hydrogen bond.

Structural comparison of ethylenediamine platinum(II) complexes containing thiourea and its di- and tetramethyl substituted derivatives

Three new platinum(II) complexes, [Pt(en)(tu)2](NO3)2 (1), [Pt(en)(dmtu)2] (NO3)2 (2) and [Pt(en)(tmtu)2](NO3)2 (3) (where en = ethylenediamine, tu = thiourea, dmtu = 1,3-dimethyl-2-thiourea and tmtu = 1,1,3,3-tetramethy-2-thiourea), have been synthesized and characterized using elemental analysis, IR spectroscopy and NMR spectroscopy. All complexes are soluble in high polarity solvents. Single crystals have been obtained by slow evaporation of methanol solution at room temperature. NMR studies show that the amide proton signals shift downfield while the thiocarbonyl carbon signals shift upfield as compared to free thioureas. These opposite chemical shifts suggest that there is a decrease in thiocarbonyl bond order and an increase in thiocarbonyl carbon-amide nitrogen bond order for the thioureas upon coordination to platinum(II). The molecular structures of the crystallized complexes have been identified by single crystal X-ray diffraction. Both 1 and 2 crystallize in the monoclinic space groups P2(1)/c and P2(1)/n, respectively, while 3 crystallizes in the orthorhombic space group C222(1). X-ray crystallographic analysis indicates that the geometry about the platinum atom is square-planar and the crystal packings are dominated by intermolecular en N − H⋅⋅⋅O (NO3 -) and tu N − H⋅⋅⋅O (NO3 -) hydrogen bonds.

Synthesis and characterization of ethylenediamine platinum(II) complexes containing thiourea derivatives. X-ray crystal structures of [Pt(en)(2-imidazolidinethione)2](NO3)2 and [Pt(en)(1-phenyl-2-thiourea)2](NO3)2

Reactions of ethylenediamineplatinum(II) nitrate with thiourea derivatives afford new complexes of the form [Pt(en)L2](NO3)2 [en = ethylenediamine, L = 1-benzyl-2-thiourea (bztu), 1-cyclohexyl-2-thiourea (chtu), 1,3-diethyl-2-thiourea (detu), 1,3-diisopropyl-2-thiourea (diptu), 1-ethyl-2-thiourea (etu), 1-heptyl-2-thiourea (htu), 2-imidazolidinethione (imt), 1-isopropyl-2-thiourea (iptu), 1-phenyl-2-thiourea (phtu), 1-(3-pyridyl)-2-thiourea (pytu), and 1-tert-butyl-2-thiourea (tbtu)]. These complexes are soluble in high polarity solvents and have been characterized by elemental analysis, IR spectroscopy and NMR spectroscopy. IR analyses reveal the characteristic vibrations of the functional groups and the nitrate counter ions. NMR studies show that the chemical shifts of proton and carbon signals of the bonded en are about the same, indicating the bonding of thioureas to the platinum(II) center exert limited trans effect on the en ligand. The observation that thioamide proton signals shift downfield and the thiocarbonyl carbon signals shift upfield as compared to the free thioureas suggests a decrease in thiocarbonyl bond order and an increase in thiocarbonyl carbon-amide nitrogen bond order upon coordination to the platinum(II) center. Good quality single crystals of [Pt(en)(2-imidazolidinethione)2](NO3)2 (7) and [Pt(en)(1-phenyl-2-thiourea)2](NO3)2 (9) are grown by slow evaporation of methanol solution at room temperature. Their molecular structures have been identified by the single crystal X-ray diffraction. Complex 7 crystallizes in the orthorhombic space group Pccn whereas 9 crystallizes in the monoclinic space group P2(1)/n. X-ray crystallographic analysis indicates that the geometry about the platinum atom is square-planar and the crystal packings are dominated by intermolecular en NH⋯O (NO3) and thioureas NH⋯O (NO3) hydrogen bonds. The two imidazole rings in 7 and the two phenyl rings in 9 are oriented above and below the PtN2S2 plane, respectively, to minimize the steric interaction.

Crystal Structure of a Bis[1-(benzothiazole-2yl-2<i>κN</i>)(2-Pyridylmethyliden-1<i>κN</i>)(hydrazino-2<i>κN)</i>] Cobalt(II) Complex

The Schiff base 1-(benzothiazol-2-yl)(2-pyridylmethylidene)hydrazine (HL) was synthesis via a condensation of 1-(benzo[d]thiazol-2-yl)hydrazine and 2-pyridine carboxaldehyde in methanol in 1:1 molar ratio reaction. The crystal structure of a mononuclear complex Bis[1-(benzothiazole-2yl-2κN)(2-pyridylmethyliden-1κ<I>N</I>)(hydrazino-2κ<I>N</I>)] cobalt(II) complex (1) (CoC₂₆H₂₀N₈S₂) was obtained by the reaction of HL with Co(CH₃COO)₂.4H₂O, in 2:1 ratio, in methanol at room temperature. The ligand and the complex are characterized by IR, and physical measurement. The spectroscopic study shows that the Schiff base possesses five potential donor sites. Upon coordination the results show that the ligand acts in tridentate mode. Suitable crystals of the compound 1 were grown by slow evaporation of methanol solution for one week. The structure of 1 was elucidated by X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system with a space group of <I>P</I>2₁/c. The asymmetric unit of compound 1 contains a mononuclear complex in which the cobalt ion is coordinated to two monodeprotonated molecules of the Schiff base. Each of the ligand molecule acts through three nitrogen atoms. The Co(II) center is hexacoordinated and the environment is best described as a distorted octahedral geometry. The two ligand molecules occupy mean planes which are quasi-perpendicular with a dihedral angle of 89.77(2)°. Each molecule of complex is connected to its neighbor via hydrogen bond of type C–H•••S resulting in chains along <i>b</i> axis.

Zinc(II) halide complexes with 2-methoxyaniline ligand: Synthesis, characterization, thermal analyses, crystal structure determination and luminescent properties

Three new mononuclear zinc(II) complexes, [Zn(2-MeO-C6H4NH2)2X2] (X is Cl in 1, Br in 2 and I in 3), were prepared from the reactions of ZnX2 with 2-methoxyaniline (2-MeO-C6H4NH2) ligand in methanol. Suitable crystals of these complexes were obtained for X-ray diffraction measurements by slow evaporation of methanol solution at room temperature. The three complexes were thoroughly characterized by thermogravimetric analysis, elemental analysis (CHNO), spectral methods (IR, UV–Vis, 13C{1H}NMR, 1H NMR and luminescence), and single crystal X-ray diffraction. The X-ray structural analysis indicated that in the structures of these complexes, the zinc(II) cation is four-coordinated in a distorted tetrahedral configuration by two N atoms from two 2-methoxyanyline ligands and two halide anions. Also, in these complexes intermolecular interactions, for example NH⋯X hydrogen bonds (in 1–3), CH⋯X hydrogen bonds (in 3), CH⋯π interactions (in 1 and 2) and π⋯π interactions (in 3), are effective in the stabilization of the crystal structures. In addition, the luminescence spectra of all complexes in methanolic solution show that the intensity of their emission bands is stronger than that for free 2-methoxyaniline ligand.

Spectral, thermal, structural and quantum chemical calculations of 3,5-dimethyl-1H-pyrazol-2-ium-3-hydroxy-2,4,6-trinitrophenolate - A new organic proton transfer crystal

Single crystals of a new proton transfer optical material, 3,5-dimethyl-1H-pyrazol-2-ium-3-hydroxy-2,4,6-trinitrophenolate (DPHTP), were obtained using slow evaporation of methanolic solution containing 1:1 M quantities of 3,5 dimethyl-1H-pyrazole and 3-hydroxy 2,4,6-trinitro phenol (styphnic acid). Asymmetric unit of DPHTP contains a univalent 3,5- dimethylpyrazolium cation with a univalent 3-hydroxy-2,4,6-trinitrophenolate anion. The various types of carbon atoms and protons in the compound were established using 1H and 13C NMR spectral studies. Thermal stability and decomposition pattern of DPHTP were studied by TG/DTA. The optical nonlinearities of DPHTP have been investigated by Z-scan technique with He-Ne laser radiation of wavelength 632.8 nm. The equilibrium optimized geometry, the first order hyperpolarizability calculations, molecular electrostatic interactions, frontier molecular orbital analysis, Mulliken population analysis have been calculated by density functional theoretical (DFT) method with (B3LYP)/6-311++G(d,p) level of basis set. First order hyperpolarizability (β) of DPHTP is 22 times greater than that of urea.

Synthesis, characterization, and X-ray structure of n'-(2-hydroxy-5-methylbenzylidene)-4-trifluoromethylbenzohydrazide and its dioxidomolybdenum(vi) complex with catalytic property

ABSTRACTA new hydrazone compound N’-(2-hydroxy-5-methylbenzylidene)-4-trifluoromethylbenzohydrazide (H2L) was prepared. Based on H2L, a new dioxidomolybdenum(VI) complex [cis-MoO2L(MeOH)], was obtained. Single crystals of H2L and the complex were obtained by slow evaporation of methanolic solution containing the compounds, and were characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction techniques. The geometry around the molybdenum center is distorted octahedral in which the tridentate benzohydrazone ligand with two anionic oxygens and one neutral imine nitrogen occupies meridional position. The octahedral geometry of the cis-dioxomolybdenum center is additionally completed by a coordinated methanol solvent molecule. The complex was tested for the homogeneous oxidation of various olefins.

Sonochemical synthesis of a new nano-scale 1D copper organic coordination polymer; thermal and spectroscopic characterizations

ABSTRACTSingle crystal of a new one-dimensional copper organic coordination polymer, 1D-CuOCP, [Cu(HL)NO3]n (1) (H2L = [2-[1-(2-hydroxy-propylimino)-ethyl]-phenol]) and its nanostructure, have been synthesized by slow evaporation of methanol solution of compound (1) and sonochemical process respectively. Nanostructure of the complex was characterized by X-ray powder diffraction (XRD), FT-IR spectroscopy and scanning electron microscopy (SEM) and the structure of compound 1 was determined by single-crystal X-ray diffraction. Thermal stability of compound 1 in its nanosize form has also been studied by thermal gravimetric analysis (TGA). The effect of concentration of initial reagents on size and morphology of nanostructured compound 1 has been examined. The brightness of this study is to use the nanostructure of 1D-CuOCP as precursor to prepare single phase CuO nanoparticles via a solid-state decomposition procedure. Characterization methods confirmed that CuO nanoparticles with an average diameter of 40 nm were obtained from direct calcination of the precursor at 500°C under air.

Synthesis, Characterization, and X-Ray Structure of [cis-MoO2L(MeOH)] (L = N′-(5-Chloro-2-Hydroxybenzylidene)-3-Chlorobenzohydrazide) and Its Catalytic Property

The synthesis and characterization of [cis-MoO2L(MeOH)] (L = N′-(5-chloro-2-hydroxybenzylidene)-3-chlorobenzohydrazide) are described. The dioxomolybdenum complex was prepared from 1:1 reaction mixture containing the benzohydrazone ligand and MoO2(acac)2. Orange single crystals were obtained by slow evaporation of methanolic solution containing the complex, and were characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction techniques. The geometry around the molybdenum center is distorted octahedral in which a tridentate benzohydrazone ligand with two anionic oxygens and one neutral imine nitrogen occupies meridional position. The octahedral geometry of the cis-dioxomolybdenum center is additionally completed by a coordinated methanol solvent molecule. The complex was tested for the homogeneous oxidation of various olefins.

Growth and characterization of Hexakis(thiourea)nickel(II) nitrate crystals

Single crystals of hexakis(thiourea)nickel(II) nitrate [Ni(SC(NH2)2)6](NO3)2 are grown by slow evaporation of methanolic solution at room temperature. Structural analysis by single crystal X-ray diffraction analysis reveals that the crystal belongs to monoclinic system with space group C2/c and the cell parameters are a=22.046(2)Å, b=9.3325(4)Å, c=16.221(2)Å, Z=8. The metal is coordinated by six thiourea groups with Ni–S–C bond angles ranging from 114.81° to 116.85° and Ni–S bond lengths lying in the range 2.35 to 2.61Å in a distorted octahedral geometry. The interesting feature observed in this study is that although it crystallizes in centrosymmetric structure, contrary to expectations, it exhibits a positive second harmonic generation (SHG) result, quite likely due to the change in stereochemical arrangement. An Nd:YAG laser with a modulated radiation of 1064nm directed on the powdered sample leads to local noncentrosymmetry and this could be due to the loss of thiourea ligands resulting in tetrakis(thiourea)nickel(II) complex causing green light emission. The powder X-ray diffraction study reveals the crystallinity of the grown material. The vibrational patterns in FT-IR clearly evidence the complex formation. Thermogravimetric analysis (TG) reveals the purity of the sample and no decomposition is observed up to the melting point. The crystal is further characterized by diffused reflectance spectroscopy, dielectric studies and microhardness analysis.

Growth and characterization of cinnamic acid–urea single crystal

A single crystal of cinnamic acid–urea was grown by slow evaporation of methanol solution at room temperature. In this research, many analytical methods such as FTIR, second harmonic generation, NMR, and TG–DTA were used. The presence of title compound in the crystal lattice has been qualitatively determined by FTIR analysis. Thermal stability of the grown crystals was evaluated by TG-DTA. Incorporation of urea increases the thermal stability insuring the suitability of material for possible non-linear optical application up to 180 °C.

Growth and characterization of mercury cinnamate single crystal

Single crystals of mercury cinnamate were grown by slow evaporation of methanol solution at room temperature. The effect of mercury on the electronic structure of cinnamic acid was studied. The grown mercury cinnamate single crystals were characterized by UV, FTIR and TG-DTA. TG curve of mercury cinnamate exhibits higher thermal stability compared with cinnamic acid which was also confirmed by DTA curve. The spectroscopic studies give evidences of the distribution of the electronic charge in molecule, the delocalisation of π electrons and the reactivity of metal complexes. The Second harmonic generation efficiency is more pronounced in the presence of mercury dopant in the growth medium.

Thermal, UV and FTIR spectral studies in alkali metal cinnamates

A single crystal of sodium and potassium cinnamates was grown by slow evaporation of methanol solution at room temperature. The effect of metals sodium and potassium on the electronic structure of cinnamic acid was studied. In this research many analytical methods such as FTIR, UV, second harmonic generation (SHG) and TG–DTA were used: The spectroscopic studies lead to conclusions containing the distribution of the electronic charge in molecule, the delocalisation of π electrons and the reactivity of metal complexes. The SHG efficiency is more pronounced in the presence of sodium and potassium dopant in the growth medium. Incorporation of sodium and potassium increase the thermal stability ensuring the suitability of material for possible non-linear optical (NLO) application up to 180 °C.

Synthesis, Growth and Characterization of 4-Benzeneazoaniline Single Crystal

A new organic nonlinear optical material 4-Benzeneazoaniline (C12H11N3) was synthesized by diazotization and diazocoupling mechanisms. Single crystal of 4-Benzeneazoaniline was grown by slow evaporation of methanol solution at room temperature. Transparent crystals with size up_to 13x4x4 mm 3 were obtained. Single crystal X-ray diffractometer was utilized to measure the unit cell parameters and to confirm the crystal structure. The structure of compound was further confirmed by FTIR, 1 H & 13 C NMR and mass spectral analyses. The UV-Vis-NIR result shows that the crystal has a sharp cut off at 220 nm and is nearly 75% transparent over a wide wavelength range enabling it for application in the UV region. The optical energy gap of 4Benzeneazoaniline was found to be 3.4 eV. Thermal properties of crystals were investigated using thermogravimetric and differential scanning calorimetric analyses, which indicated that the material does not decompose before melting. The NLO test confirms the second harmonic signal generation in the sample.

Imino-Diels-Alder Adducts. Part XIII. Polymorphism in Pyrano [3,2-c] Quinolines

Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. Rectangle plate-like crystals have a triclinic (P $$ \ifmmode\expandafter\bar\else\expandafter\=\fi{1} $$ ) structure, with one molecule in the asymmetric unit, a = 8.2299(5) A, b = 9.7774(6) A, c = 11.0047(7) A, α = 65.718(1)°, β = 75.699(1)° and γ = 71.617(1)°, while, long needle-like crystals exhibit a monoclinic (C2/c) crystal structure in which two independent molecules comprise the asymmetric unit, a = 32.285(3) A, b = 9.4045(7) A, c = 22.804(2) A and β = 114.965(1)°. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R2 2(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form. Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R2 2(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form.

Crystal structures and cytotoxicity of isopropylamine Pt(II) complexes: A trinuclear squarato-bridged [Pt3(μ2-C4O4)3(H2NPri)6] · 3H2O and a mononuclear cis-[Pt(NO3)2(H2NPri)2

Crystals of a novel platinum(II) complex with squarato ligand, [Pt3(μ2-C4O4)3(H2NPri)6]·3H2O (1) (H2NPri=ipa), have been isolated from the aqueous solution of cis-[Pt(H2O)2(H2NPri)2]SO4 and barium squarate. Slow evaporation of methanol solution of cis-[Pt(NO3)2(H2NPri)2] (2) resulted in crystallization of nitrato complex.The single crystal X-ray diffraction method was used to determine structures of 1 and 2. Complex 1 crystallizes in a triclinic space group P1¯ with a=11.17380(10)Å, b=14.4535(2)Å, c=14.8010(2)Å, α=86.0901(10)°, β=78.4343(11)°, γ=69.1915(5)°, and complex 2 in a monoclinic space group P21/n, with a=10.1161(2)Å, b=9.9188(2)Å, c=13.3766(2)Å, β=102.7360(7)°. The X-ray structure analysis revealed that three platinum atoms in 1 are connected with three squarates which adopt bis(unidentate) binding modes. The squarato ligands span relatively long intramolecular Pt⋯Pt distances (4.8842(3)–5.2699(3)Å). A pair of cis positioned isopropylamine ligands completes a square planar coordination sphere of each Pt(II) ion. The square–planar coordination of complex 2 consists of two cis positioned isopropylamine ligands and two nitrato ligands.The results of cytotoxicity assay of trimer 1, monomer 2 and cis-diamminedichloroplatinum(II) (cisplatin) performed on human bladder tumor cell line T24 provide evidence that complex 2 is less cytotoxic compared to cisplatin and that the survival of tumor cells after exposure to 1 was minimally reduced.

Forthcoming papers

Reactions of ethylenediamineplatinum(II) nitrate with thiourea derivatives afford new complexes of the form [Pt(en)L2](NO3)2 [en = ethylenediamine, L = 1-benzyl-2-thiourea (bztu), 1-cyclohexyl-2-thiourea (chtu), 1,3-diethyl-2-thiourea (detu), 1,3-diisopropyl-2-thiourea (diptu), 1-ethyl-2-thiourea (etu), 1-heptyl-2-thiourea (htu), 2-imidazolidinethione (imt), 1-isopropyl-2-thiourea (iptu), 1-phenyl-2-thiourea (phtu), 1-(3-pyridyl)-2-thiourea (pytu), and 1-tert-butyl-2-thiourea (tbtu)]. These complexes are soluble in high polarity solvents and have been characterized by elemental analysis, IR spectroscopy and NMR spectroscopy. IR analyses reveal the characteristic vibrations of the functional groups and the nitrate counter ions. NMR studies show that the chemical shifts of proton and carbon signals of the bonded en are about the same, indicating the bonding of thioureas to the platinum(II) center exert limited trans effect on the en ligand. The observation that thioamide proton signals shift downfield and the thiocarbonyl carbon signals shift upfield as compared to the free thioureas suggests a decrease in thiocarbonyl bond order and an increase in thiocarbonyl carbon-amide nitrogen bond order upon coordination to the platinum(II) center. Good quality single crystals of [Pt(en)(2-imidazolidinethione)2](NO3)2 (7) and [Pt(en)(1-phenyl-2-thiourea)2](NO3)2 (9) are grown by slow evaporation of methanol solution at room temperature. Their molecular structures have been identified by the single crystal X-ray diffraction. Complex 7 crystallizes in the orthorhombic space group Pccn whereas 9 crystallizes in the monoclinic space group P2(1)/n. X-ray crystallographic analysis indicates that the geometry about the platinum atom is square-planar and the crystal packings are dominated by intermolecular en NH⋯O (NO3) and thioureas NH⋯O (NO3) hydrogen bonds. The two imidazole rings in 7 and the two phenyl rings in 9 are oriented above and below the PtN2S2 plane, respectively, to minimize the steric interaction.