X-ray powder diffraction and Raman spectroscopy studies of phase transitions in zinc(II) hexaaquonitrate below 300 K

Structural phase transitions in zinc(II) hexaaquonitrate have been studied below 300 K by Raman spectroscopy and X-ray powder diffraction. Changes of A1 nitrate and O H bands together with diffractograms as functions of temperature are presented. The compound undergoes several transitions and four previously unreported modifications were found and characterized.     

X-ray diffraction studies on molten zinc bromide at high pressure

X-ray diffraction investigations into molten zinc bromide at temperatures of 450 °C and 500 °C and pressures up to 3000 bar are presented. The distinct terms and the total atom pair correlation functions of ZnBr₂ are presented and the effect of the pressure on the structure is discussed. The results are compared with previous experiments on molten ZnCl₂.     

X-ray diffraction analysis of (Ph2PO)2

The title compound (Ph2PO)2 is analyzed by single crystal X-ray diffraction analysis. The crystals are monoclinic, space group P2(1)/n with a = 9.5112(19) Å, b = 11.161(2) Å, c = 9.5487(19) Å, α = 90°, β = 91.65(3)°, γ = 90°, V = 1013.2(3) ų, Z = 2, F(₀₀₀) = 420, Dc = 1.319 g cm^–3, μ = 0.232 mm^?1, the final R = 0.0818, and wR = 0.2259. A total of 7954 reflections were collected, of which 1758 were independent (R_int = 0.0542). In the crystal packing diagram, intermolecular C—H···O hydrogen bonds stabilize the solid state of the title compound.     

X-ray diffraction investigation of two mesomorphic copper(II) complexes of tetra-4-[(4-alkoxycarbonyl)phenyleneoxy]phthalocyanine

The mesomorphism and supramolecular structure of two homologues of copper tetra-4-[(4-alkoxycarbonyl)phenyleneoxyl]phthalocyanines are investigated using optical polarizing microscopy, differential scanning calorimetry (DSC), and X-ray diffraction. It is revealed that both homologues, which contain four and nine carbon atoms in aliphatic fragments of the lateral substituents, exhibit thermotropic columnar mesomorphism with a hexagonal arrangement of ordered columns (Col _ho). A change in the length of the aliphatic fragment has no noticeable effect on the mesophase type and leads only to variations in the parameters of the hexagonal lattice formed by the columns. The glass transition temperature of the homologue with n = 4 (T _g = 88°C) is considerably lower than that of the homologue with n = 9 (T _g = 88°C). It is established that the introduction of the cyclic fragment into the lateral substituent substantially affects the type of column packing as compared to the copper tetra-4-[(n-alkoxy)carbonyl]phthalocyanines studied in our earlier works. The assumption is made that this difference is associated, in particular, with the specific features of the penetration of the lateral substituents of the adjacent columns either in the presence or in the absence of the cyclic fragment in the lateral substituent.     

Synthesis and X-ray diffraction study of palladium(II) 1,3-diphenyl-5-(benzothiazol-2-yl)formazanate

The behavior of 1,3-diphenyl-5-(benzothiazol-2-yl)formazan as a bidentate ligand in the synthesis of the mononuclear palladium complex was investigated using slow diffusion. According to the X-ray diffraction study, the PdN4 coordination unit has a distorted square structure. The ligands form two six-membered chelate rings formed through the N1 and N4 atoms of the formazan fragment.     

Crystal structures and spectroscopic properties of copper(II) and zinc(II) complexes with the macrocycle 1,4,7-tris(2-pyridylmethyl)-1,4,7-triazacyclononane

Two novel transition-metal copper and zinc complexes [(CuL)₂]·(ClO₄) (1) and [(ZnL)]·(ClO₄)₂ (2) (L = 1,4,7-tris(2-pyridylmethyl)-1,4,7-triazacyclononane) have been synthesized and structurally determined. The two complexes are both crystallized in monoclinic space group P2(1)/c with a = 14.318(4), b = 17.214(5), c = 22.403(7) Å, = 93.096(6)°, V = 5522(3) ų, and Z = 4 for 1 and a = 9.371(2), b = 17.615(4), c = 17.579(4) Å, =104.070(4)°, V = 2814.6(11) ų, and Z = 4 for 2. The center metal ions are coordinated to six nitrogen atoms, three of which are from triazacyclononane and other three from the pendant-arms 2-pyridylmethyl, forming a slightly distorted octahedral geometry. Two complexes have been characterized by element analysis, infrared spectroscopy, and the UV–Vis and ESR spectra for 1 have also been determined.     

X-ray diffraction study of 1,5-bis(2-Formylphenoxy)pentane

1,5-Bis(2-Formylphenoxy)pentane was studied by X-ray diffraction. There are two crystallographically independent molecules with similar geometric parameters in the asymmetric unit of the crystal structure. The molecules occupy special positions on a rotation axis.