Crystal structure and thermal analysis of 1,5-diammonium-2-methyl pentane sulfate monohydrate

Chemical preparation, x-ray single crystal, and thermal analysis of C₆H₁₈N₂SO₄·H₂O (denoted DMPS) are described. The compound crystallizes in the triclinic system with P space group. Its unit cell dimensions are a = 5.826(1) Å, b = 10.014(1) Å, c = 11.221(1) Å, = 66.716(1)°, = 84.395(1)°, = 83.759(1)°, V = 596.7(1) ų, and Z = 2. The DMPS structure is built up from inorganic chains parallel to the a axis and linked via O(W)-H···O hydrogen bonds. These chains are interconnected by organic groups. Thermal analysis reveals the presence of one water molecule in the structure and shows a reversible weak phase transition.     

Crystal structure, thermal analysis, and IR spectrometric investigation of bis(tert-butylammonium) sulfate

Chemical preparation, X-ray single crystal, thermal analysis, and IR spectrometric investigation of (C₄H₁₂N)₂SO₄, denoted tBAS, are described. The compound crystallizes in the monoclinic system with C2/c space group. Its unit cell dimensions are a = 11.1585(5) Å, b = 6.2148(4) Å, c = 20.070(1) Å, = 102.004(4)°, V = 1361.4(1) ų, and Z = 4. The crystal structure of tBAS can be described as a typical thick layered organization built by all the components of the structure and centered by planes z = 1/4 and 3/4. Connection in these layers are established by N—H···O hydrogen bonds. Thermal analysis shows a reversible weak phase transition.     

Structure, thermal behavior, and IR investigation of a new organic sulfate

[1-(2-ammoniumethyl) piperazinium] sulfate denoted PIPS has a monoclinic unit cell. The parameters are: a = 6.6521(3), b = 7.8756(5), c = 19.197(1) Å, = 94.43(1)° and the space group is P2₁/n. The preparation, thermal analysis, and IR spectrometric investigation are described. The PIPS structure exhibits a complex three-dimensional network of H-bonds connecting all its components.     

Structure, thermal behavior, and IR investigation of bis(3-amino-1,2,4-triazolium)monohydrogen monophosphate

Chemical preparation, calorimetric studies, crystal structure, and IR spectrometric investigation of (C₂H₅N₄)₂HPO₄, denoted ATZP, are described. The compound crystallizes in the monoclinic system with C2/c space group. Its unit cell dimensions are a = 13.589(2) Å b = 11.105(2) Å c = 15.734(3) Å = 104.68(2)°, V = 2296.8(7) ų, and Z = 8. The structure of the title compound consists of a three dimensional network of H-bonds connecting all its components. The IR spectrum of ATZP is reported and discussed on the basis of group theoretical analysis.     

Crystal structure,thermal behavior and IR investigation of 1,6‐diammonium hexan dihydrogenodiphosphate dihydrate

Physicochemical properties of (C₆H₁₈N₂)H₂P₂O₇·2H₂O denoted DHDP are discussed on the basis of X‐ray crystal structure investigation. The compound crystallises in the triclinic system with P space group. Its unit cell dimensions are a = 13.719(1) Å, b = 14.188(3) Å, c = 9.177(1) Å, α = 108.50(1)°, β = 91.11(1)°, γ = 115.47(1)°, V = 1503.8(4) ų and Z = 4. The structure has been solved using direct methods and refined to a reliability R factor 0.0401 for 4778 reflections. The main feature of the atomic arrangement of DHDP is the existence of infinite rows, parallel to the c direction of the unit cell, composed of H₂P₂O₇ groups. These phosphoric rows are organised to create, with the help of the organic cation, large rectangular channels in which the unstable water molecule are located since they have high thermal parameters. Phosphoric anions and organic cations have no internal symmetry. DSC and TG‐DTA show that dehydration occurs in one step. Such dehydration process may be related to the similar environments on the water molecules residing in the channel. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure,thermal analysis and IR spectroscopy investigations of N,N‐dimethyl‐1,3‐propanediammonium monohydrogenmonophosphate trihydrate

A new organic monohydrogenmonophosphate (C₅H₁₆N₂)HPO₄.3H₂O (abbreviate as MPAP) is prepared by reacting H3PO4 with N, N‐dimethyl‐1,3‐propanediamine. This compound crystallizes in the orthorhombic crystal system, space group Pca2₁. Unit cell parameters are a % 8.1445(1) Å, b % 11.7734(2) Å, c % 12.9021(2) Å, with, Z % 4 and ρ_m % 1.31 g cm⁻³. The structure was solved, using the direct methods and refined against F² to a reliability R factor of 0.0257. Three types of hydrogen bonds participate to the structural cohesion: O(P)—H…O, O(W)—H…O and N—H…O. The first one connects HPO₄ groups in infinite chains. This organization of the phosphoric groups creates voids in which are located the water molecules which are themselves connected by the second type of hydrogen bonds to the adjacent phosphoric groups that lead to a typical layer organization of a polyanion [HPO₄.(H₂O)₃ ]²ⁿ⁻_n. The third hydrogen bond type is responsible for the cohesion between the two‐dimensional polyanions. Thus, a framework in a threedimensional way is then created. The thermal decomposition of MPAP shows a large endothermic effect corresponding to the elimination of the water molecules and a set of endotherms which are probably due to the evolution of ammonia from the structure and the decomposition. The title compound was also characterized by IR spectroscopy, the interpretation of the spectra is based on theoretical analyses and literature data. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure,thermal analysis,and IR spectroscopic investigation of bis(2-amino-6-methyl) pyridinium sulfate

Synthesis, crystal structure refinement, phase transitions studied by thermal analysis, and IR spectroscopic investigation of 2C₆H₉N₂ < eqid2 > ⋅SO₄²⁻ are reported. The title compound crystallizes in the monoclinic space group C2/c (no. 15) with a = 10.5068(4) Å, b = 10.2225(5) Å, c = 14.0422(7) Å, and β = 104.489(3)^∘. A crystal packing diagram shows layers built by all the components of the structure and centered by planes z = 1/4 and 3/4. The pyridine substituents stack forming channels parallel to the c direction with dimensions of 4.163(1) Å and 5.148(4) Å. Thermal analysis shows that the anhydrous compound possesses an irreversible weak phase transition.     

Crystal structure,thermal analysis and IR spectrometric investigation of bis (2‐amino‐6‐methyl) pyridinium sulfate

The synthesis method, crystal structure determination, phase transitions studied by thermal analysis and IR spectrometric investigation of 2C₆H₉N₂⁺.SO₄^2– are reported. The compound crystallizes in the monoclinic space group C2/c (no. 15) with a = 10.5068(4) Å, b = 10.2225(5) Å, c = 14.0422(7) Å, and β = 104.489(3)°. The atomic arrangement can be described by layers built by all the components of the structure and centered by planes z = 1/4 and 3/4. The organic molecules form channels parallel to the c direction with dimensions of 4.163(1)Å and 5.148(4)Å. Thermal analysis shows that the anhydrous compound presents an irreversible weak phase transition. The IR study, based on theoretical analyses and on the literature data allows the interpretation of the IR spectrum. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal growth and characterization of PbI2‐AgI binary system

The crystals of the binary system PbI₂‐AgI (PIAI) were obtained by heating the mixture of individual PbI₂ (PI) and AgI (AI) placed at 30° angle in the horizontal tubular furnace of variable temperature zone. The crystals were characterized by powder XRD, TG/DTA, FT‐IR and SEM. The 3.37% weight loss in the sample after heating at 853 K is due to the presence of water molecules absorbed (3446 cm^–1) by the crystals during sintering and cooling process. The cell parameters of the crystal were determined using the powder X‐ray data. The PbI₂‐AgI crystallizes in monoclinic system a = 10.799 (±0.009), b = 7.492 (±0.004), c = 6.929(±0.004) Å and α = 90°, β = 108.04(±0.073) γ = 90°, V = 533.18 ų. The electrical conductivity measurements of the crystals showed a sudden change in the current value at the temperature range 385–393 K. The activation energy before and after the drift was found to be 0.49 and 0.35 eV respectively. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure of aluminum sulfate hexadecahydrate and its morphology

A single‐crystal structure of aluminum sulfate hexadecahydrate (Al₂(SO₄)₃·16H₂O) was captured with a polarizing microscope. The structure was similar to a hexagonal plate and consistent with the predicted morphology derived from the modified AE model. An octagonal plate morphology was first obtained in a vacuum but was transformed into hexagonal plate‐like when the effect of the solvent with two disappearing {1 1 0} and {1 0 −1} faces was considered.     

Crystal structure of a novel bis(guanidiniums) compound incorporated by sulfate anion

Crystal structure of a novel bis(guanidiniums) compound 1 by sulfate anion and water, C₁₁H₂₀N₆OSO₄H₂O, was measured by X-ray crystallographic analysis with an imaging plate method. It possesses space group P2₁/c, with a = 7.6433(15), b = 19.447(4), c = 12.115(2) Å, = 107.81(3)°, and _calc = 1.420 mg/m³ for Z = 4. Crystal data indicate that the architecture network is formed through hydrogen bonds, electrostatic interactions, and arene–arene stacking interaction among the bis(guanidiniums) compound, the sulfate anion and water molecule.     

Structure, thermal behavior, and IR investigations of (C6H9N2)H2PO4

Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy studies of a new dihydrogenmonophosphate associated to an organic cation, the 3-(ammoniummethyl)pyridine dihydrogenmonophosphate (denoted as AMPP) are described. The AMPP crystallizes in the monoclinic system with P2₁/c space group. The unit cell dimensions are a = 5.8465(2) Å, b = 19.9776(9) Å, c = 7.3103(3) Å, = 90.848(3)° with V = 853.74(4) ų and Z = 4. The structure has been solved using direct method and refined to a reliability R factor of 0.0393. The structure of AMPP includes three types of hydrogen bonds. The first one, O H O, links the H₂PO₄ groups to form infinite inorganic chains [H₂PO₄]n ^n–, parallel to the c axis. The two other types, O H N and N H O assemble inorganic chains so as to build up a three-dimensional arrangement.     

Structural,thermal and optical studies on 2‐naphthol crystals

Single crystals of 2‐naphthol was grown in slow evaporation solution growth technique. Grown crystals were characterized by various characterization techniques. Powder X‐ ray diffraction studies reveal that the grown crystal belongs to monoclinic system with noncentrosymmetric space group. Vibrational bands of the various functional groups and their significance were investigated by analyzing the vibrational spectra. Melting point and the decomposition temperature of the grown crystal was premeditated from the thermal analysis. From the UV‐VIS‐NIR spectrum the electronic excitation mechanism and the transmittance abilities of the crystal was studied. Theoretical value of first static hyperpolarizability was calculated and compared with urea. Second harmonic generation efficiency of the crystal is 0.6 times that of KDP. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis, Crystal Structure, Thermal Behavior and IR Characterization of Pentacarbonyl(4-methylpyridine)chromium(0) Complex

Abstract  Pentacarbonyl(4-methylpyridine)chromium(0) complex was isolated from n-hexane solution as yellow plate-like crystals and characterized by using X-ray crystallography. It crystallizes in the orthorhombic system with the space group Cmcm and Z = 4. The unit cell parameters are a = 11.737(1) ?, b = 12.857(2) ?, c = 8.465(1) ?. The single crystal X-ray structure of the complex shows that the coordination sphere around the chromium central atom is slightly distorted octahedron, involving the 4-methylpyridine (4-mp), ligand as a monodentate N-donor ligand and five carbonyl groups. The four equatorial CO groups in the complex, with the Cr–C2 distance of 1.886 Ǻ, are slightly bent away from the 4-methylpyridine ligand with the N–Cr–C2 angle of 91.69°. The pyridine ring plane makes an angle of 135.17° with the Cr–N–CO bond axis. The thermal analysis (differential thermal analysis and thermal gravimetry) and IR spectra of the complex indicated that the compound undergoes complete decomposition to form the Cr₂O₃ as the final decomposition product. Index Abstract  The crystal structure of pentacarbonyl(4-methylpyridine)chromium(0) complex has been determined and its thermal behavior has also been studied.      

Crystal structure and spectroscopy of bis-[bis(2-benzimidazolyl)propane]copper(II) bis(triflate)monohydrate, a copper complex with a geometry intermediate between tetrahedral and square planar

The structure of a mononuclear copper(II) compound with the ligand bis(2-benzimidazolyl)propane (abbreviated as tbz) is reported. The compound [Cu(tbz)₂](CF₃SO₃)₂(H₂O) crystallizes in the triclinic space group P , with a = 12.363(6), b = 13.218(9), c = 15.365(8) Å, = 82.74(5), = 68.04(4), = 65.30(5), and Z = 2. The Cu(II) atom has a geometry intermediate between tetrahedral and square planar, consisting of four nitrogen atoms of two tbz ligands. The Cu—N—Cu angles are about 135°, while the dihedral angle between them amounts to 62° (0° for square planar and 90° for a tetrahedron). Ligand field bands are observed at 10.2 × 10³, 13.8 × 10³, and 20.3 × 10³ cm^–1, while the most characteristic infrared vibrations of the triflate anion are observed at 1273, 1260, 1238, 1221, 1171, and 1157 cm^–1.     

Crystal structures and vibrational spectra of racemic and chiral 4-phenyl-1,3-oxazolidine-2-thione

The crystal structures of (rac)- and (R)-4-phenyl-1,3-oxazolidine-2-thione (4-POT) have been determined by X-ray diffraction. The structure of (rac)-4-POT is monoclinic P2₁/n with a = 11.9096(9) Å, b = 5.9523(6) Å, c = 12.3563(8) Å, = 91.054(6)°, V = 875.8(1) ų, and Z = 4. The structure of (R)-4-POT is orthorhombic P2₁2₁2₁ with a = 7.7197(6) Å, b = 21.603(2) Å, c = 5.4613(9) Å, V = 910.8(2) ų, and Z = 4. (rac)-4-POT and (R)-4-POT crystals are shown to have different hydrogen-bonding patterns. In the racemic crystals, the enantiomeric (R)- and (S)-4-POT molecules are connected to form a cyclic dimer via the N–H S hydrogen bond of the cis thioamide moiety [N Sⁱ 3.438(2) Å, N–H Sⁱ 176(2)° symmetry code: (i) 1 – x, 1 – y, 1 – z]. In the chiral (R)-4-POT crystals, the N–H S intermolecular hydrogen bond forms a zigzag chain around the twofold screw axis [N Sⁱⁱ 3.347(3) Å, N–H Sⁱⁱ 161(3)° symmetry code: (ii) 1/2 + x, 1/2 – y, 2 – z]. Observed difference of 46°C in the melting points between the (rac)-4-POT and (R)-4-POT crystals is correlated with difference in the crystal packing. Vibrational spectra of (rac)- and (R)-4-POT crystals are discussed both in the solid state and in solution.     

Crystal structure and phase transition of single crystalline CsNH2SO3

Differential scanning calorimetry (DSC) and X‐ray diffraction measurements have been performed on cesium sulfamate CsNH₂SO₃ single crystal. Two distinct endothermic peaks in the DSC curves are observed at 330 and 436 K. It is pointed out that the peak at 330 K is attributed to the structural phase transition, and the other peak at 436 K is associated with the thermal decomposition of the crystal. The structures in room‐ and high‐temperasture phases are determined, and the space group of the sample crystal is found to change from monoclinic P 2₁/c to orthorhombic Pnma. The structure of the room‐temperature phase consists of two different types of N‐H···O hydrogen bond, but in the high‐temperature phase there is no specific hydrogen bond between the NSO₃ pseudo‐tetrahera. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure and spectroscopic studies of a new organic monohydrogenmonophosphate dihydrate

The crystal synthesis and structure of a new organic monohydrogenmophosphate (3,4‐Cl₂‐CH₂C₆H₃NH₃)₂HPO₄·2H₂O are reported. This compound crystallizes in the monoclinic P2₁/n with a = 9.081(7) Å, b = 6.501(5) Å, c = 35.423(12) Å, β = 91.09(5)°, V = 2090.9(2) ų, and Z = 4. Crystal structure was solved and refined to R = 0.042, using 2543 independent reflections. It can be described by inorganic layers, including the HPO₄^‐ anions and the H₂O molecules, parallel to (a, b) planes and situated at z = 0 and z = 1/2. The interlayer spacing is occupied by the organic molecules which perform different interactions around the 3D network cohesion. A characterization of this compound by solid‐state (¹³C, ³¹P) MAS NMR and IR spectroscopies is also reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure and EPR spectra of glycilglycilglycinocopper(II)bromide sesquihydrate

The title compound, Cu(glyglygly)Br·1·5H₂O, crystallizes in the space group C2/c, with a = 21.468(7), b = 6.716(5), c = 16.166(6) Å, = 98.39°, and Z = 8. The tripeptide is bonded to one Cu(II) ion through the nitrogen [Cu–N=1.97(1)Å] and oxygen [Cu–O=2.019(8)Å] atoms of the amino end glycine residue and to another Cu(II) through one oxygen atom [Cu–O=1.931(9)Å] of the terminal carboxyl group. This give rise to covalently bonded and infinite ···–Cu–tripeptide–Cu–··· chains. These chains are linked to one another by a network of H-bonds involving the water molecules and bromide ions. The Cu(II) ion is in a distorted tetragonal pyramidal coordination polyhedron. At the corner of the base of the pyramid are the terminal glycine nitrogen and oxygen atoms of one tripeptide, a carboxylic oxygen of another tripeptide and a bromide ion. The fivefold coordination is completed with a water molecule at the top of the pyramid [Cu–Ow=2.286(9)Å]. For all orientations of the applied magnetic field the single crystal EPR spectra display a single anisotropic exchange collapsed resonance without hyperfine structure. Its position was measured in three perpendicular planes and the crystal g-tensor evaluated from the data. This tensor is interpreted in terms of the contributing Cu(II) complexes in the unit cell to deduce the principal values g₁ = 2.273, g₂ = 2.050 and g₃ = 2.131 for the molecular gyromagnetic tensor. We also discuss the magnitude of the exchange interaction between neighboring copper ions in the lattice on the basis of the features in the EPR spectra and the structural information.     

Crystal growth,thermal and optical studies of L‐histidine tetrafluoroborate: A semiorganic NLO material

L‐histidine tetrafluoroborate (L‐HFB), a semiorganic nonlinear optical (NLO) material has been synthesized and characterized by elemental analysis and FT–NMR spectroscopic studies. Solubility of L‐HFB has been determined in water and ethanol. The single crystals with dimensions 15 x 12 x 3 mm³ were grown by slow evaporation technique under two different pH conditions. The effect of pH on the morphology of the crystals have been studied. The grown crystals of both pH values has been subjected to single crystal X‐ray diffraction to determine the unit cell dimensions and morphology. The thermal stability has been analyzed by TGA and DTA. The microhardness test was carried out in (001) plane and the hardness coefficient was calculated. The birefringence values (Δ_n) were determined in the wavelength region 5540–6460 Å. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)