4-[(E)-2,6-Dichloro­benzyl­ideneamino]-3-{1-[4-(2-methyl­prop­yl)phen­yl]eth­yl}-1H-1,2,4-triazole-5(4H)-thione

In the title Schiff base compound, C21H22Cl2N4S, the triazole ring makes dihedral angles of 2.15 (11) and 87.48 (11)° with the 2,6-dichloro­phenyl and methyl­propyl­phenyl rings, respectively. Weak intra­molecular C—H⋯S and C—H⋯Cl inter­actions generate S(6) and S(5) ring motifs, respectively. In the crystal structure, centrosymmetrically related mol­ecules are linked into dimers by N—H⋯S hydrogen bonds. These dimers are arranged into sheets parallel to the ab plane and are stacked along the c axis. C—H⋯π inter­actions involving the methyl­propyl­phenyl ring and π–π inter­actions involving the dichloro­phenyl ring [centroid–centroid distance = 3.5865 (3) Å] are also observed

Effect of thiourea on the crystal structure of ammonium dihydrogen phosphate

859-862The crystal structure of thiourea mixed ammonium dihydrogen phosphate (ADP) was determined at 116(2) K. Temperature variation of thermal vibrations signifies the existence of a disordered character of atoms. The structure was solved using SHELXS-97 and refined with SHELXL-97. A direct-method solution was calculated which provided positions of non-hydrogen atoms from the E-map. Full-matrix least squares/difference Fourier cycles were performed to locate the hydrogen atoms. All non-hydrogen atoms were refined with anisotropic displacement parameters. The unique hydrogen on the nitrogen and the half-weight hydrogen on the oxygen atom were refined as isotropic contributors in the final cycles of refinement. It follows that the mechanism of the phase transition is dominated by the disorder-like motion of the NH4+  ion rather than the PO4 tetrahedro

Crystal growth and characterization of thiourea mixed ammonium dihydrogen phosphate

455-460Single crystals of thiourea mixed ammonium dihydrogen phosphate (TADP) have been grown in solution by slow evaporation technique at ambient temperature (30°C). TADP crystallises in body centered tetragonal system with unit cell parameters a= 7.4652Ǻ, b=7.4970Ǻ, c=7.5415Ǻ. The powder X-ray diffraction pattern has been recorded and indexed. The UV-Vis-NIR transmittance and FT-IR spectrum have been recorded in the range 200-1500 nm and 400-4000 cm-1, respectively. The lower cut-off wavelength is 230 nm in the UV region, which is higher than that of ADP crystal. The presence of functional groups has been confirmed by FTIR analysis. The microhardness of TADP was evaluated using Vicker's indentation method. TADP crystals are thermally stable up to 200°C and shows optical non-linearity for Nd:YAG laser at 1.064 µm wavelength. The preliminary data indicate that the harmonic generation efficiency of TADP is three times that of pure ADP. </span

<span style="font-size:13.0pt;mso-bidi-font-size: 12.0pt;line-height:115%;font-family:"Times New Roman","serif";mso-fareast-font-family: "Times New Roman";mso-ansi-language:EN-IN;mso-fareast-language:EN-IN; mso-bidi-language:HI" lang="EN-IN">Electron spin resonance in X-irradiated Ca_0.8Ba_0.2C₄H₄O₆.4H₂O single crystal</span>

603-605Barium mixed calcium tartrate tetrahydrate (CBT) single crystals with molecular formula Ca0.8Ba0.2C4H4O6.4H2O have been grown in gets by controlled diffusion technique at ambient temperature. The CBT single crystals are characterized by electron spin resonance technique. The X-irradiation of CBT single crystals gives rise to a spectrum with hyperfine complements. The maximum hyperfine splitting observed for CBT crystals may be due to the variation in the interatomic distance. The g-factor and hyperfine splitting of CBT crystal are independent of temperature. </span

Vibrational studies of gel grown antimony thiourea chloride and bismuth thiourea chloride crystals

85-88<span style="font-size: 15.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif""="">Single crystals of antimony thiourea chloride (ATC) and bismuth thiourea chloride (BTC) have been grown in gels at ambient temperature using a controlled chemical reaction method. The laser Raman and FTIR spectra of the gel grown ATC and BTC crystals have been recorded. The presence of thiourea ion, water molecules and normal mode vibrational frequencies are identified and discussed. The basic ideas regarding the normal modes of vibration, selection rules for Raman and IR spectra and hydrogen-bonding effect are constdered in brief. Molecules of water of crystallitzation are <span style="font-size:15.5pt;mso-bidi-font-size:8.5pt; line-height:115%;font-family:" times="" new="" roman","serif""="">weakly bonded in antimony thiourea chloride crystal and do not take part i<span style="font-size:13.0pt;mso-bidi-font-size:6.0pt;line-height:115%;font-family: " arial","sans-serif""="">n <span style="font-size:15.5pt;mso-bidi-font-size: 8.5pt;line-height:115%;font-family:" times="" new="" roman","serif""="">hydrogen bond formation. </span

ESR studies of X-irradiated strontium mixed calcium tartrate crystals

The electron spin resonance spectra of X-ray irradiated single crystals of strontium doped calcium tartrate tetrahydrate (CST) with molecular formula Ca0.88Sr0.12C4H4O6.4H(2)O grown in gels has been investigated. Only one species of free radical but with two magnetically unequivalent sites was observed at room temperature. The free radical was found to be the result of the splitting of a C-II bond adjacent to both the hydroxyl and carboxyl groups. The a factor was found to be slightly anisotropic. Couplings with two H nuclei, believed to be the proton of the OH group attached directly to the unsaturated asymmetric carbon atom and the proton attached directly to the: other asymmetric carbon atom of the molecule were observed. The principal g-values were found to be 2.0030, 2.0017, 2.0027. The principal elements of the nuclear coupling are 7.45, 6.59, 4.28 and 8.56, 7.22, 18.71 G, respectively. The radical was found to be very stable. (C) 2000 Elsevier Science Ltd. All rights reserved

Synthesis, Growth, and Characterization of Sodium Coordinated Glycine-Nlo Material

A new complex of the amino acid glycine has been synthesized by coordination with sodium nitrate. The title complex, Na(CH2NH2COOH)(2)NO3, crystallizes in the monoclinic space group, Cc , with parameters a = 14.331(2) Angstrom, b = 5.262(2) Angstrom, c = 9.119(2) Angstrom, beta = 119.08(1)degrees, V = 600.8(2) Angstrom(3) , Z = 4, F.W. = 159.06, D-c = 1.758 Mg.m(-3), F-000 = 324, lambda(MoKalpha) = 0.71069 Angstrom, mu = 0.228 mm(-1), R1 = 0.0481. The compound exhibits some novel structural features. The optical second harmonic generation conversion efficiency was determined using Kurtz powder technique. It was found to be twice that of Potassium Diortho Phosphate (KDP)