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41.
M. Nilofar Nissa P. G. Aravindan V. Kasinath G. Gopalakrishnan H. Merazig D. Velmurugan 《Crystal Research and Technology》2004,39(7):643-649
The title compounds (I) and (II) crystallize in the monoclinic space group P21/c and orthorhombic space group Pbca respectively. The inter‐planar angle between the two phenyl rings are 55° in I and 24.5(1)° in II. The molecular packing of the compounds I and II are stabilized by C‐H…O and C‐H…π, and N‐H…O, C‐H…O and C‐H…π interactions, respectively. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
42.
M. Yogavel P. G. Aravindan D. Velmurugan K. Sekar S. Selvi P. T. Perumal S. Shanmuga Sundara Raj H.‐K. Fun 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o394-o396
In the title compounds, C13H15N3O, (I), and C13H15N3O2, (II), the dihedral angles between the planes of the phenyl ring and the amide group are 4.1 (1) and 20.7 (1)°, respectively. The molecules adopt a fully extended conformation, aided by intramolecular interactions. The molecular structures of (I) and (II) display different crystal packing and hydrogen‐bonding networks. 相似文献
43.
M. Nilofar Nissa D. Velmurugan S. Shanmuga Sundara Raj H.‐K. Fun V. Kasinath G. Gopalakrishnan 《Crystal Research and Technology》2002,37(1):125-133
The crystal structures of two cinnamanilide derivatives 2‐methyl cinnamanilide (C16 H15 N O – compound I) and 2‐methoxy cinnamanilide (C16 H15 N O2 – compound II) are reported. In both crystal structures, the cinnamamide group is almost planar. The inter‐planar angle between the two phenyl rings are 71.6(1)° for compound I and 7.5(1)° for compound II. The N‐H…O and C‐H…O type of hydrogen bond interactions between the amide group and the carbonyl group stabilizes the molecular packing as chains in the crystal lattice. 相似文献
44.
Rajendiran Thekkel M. Kannappan Ramu Mahalakshmi Rajaram Venkatesan Rangarajan Sambasiva Rao Pillutla Govindaswamy Lakshmanan Velmurugan Devadasan 《Transition Metal Chemistry》2003,28(6):644-649
The synthesis, X-ray and e.p.r. spectral studies of a 3d–4f couple are described here. The crystal structure of [Cu(salbn)Gd(NO3)3·H2O], (2), salbn = N,N-butylenebis(salicylideaminato), has been determined by X-ray crystallography. Compound (2) crystallizes in the monoclinic system, space group p21/n, with a = 9.025(1), b = 22.912(1), c = 12.790(1) Å, = 99.36(1), Z = 4. The deviations of the four coordinating atoms (O(1)O(2)N(1) and N(2) of salbn and the copper atom is displaced from the plane in spite of the lack of any apical ligand. The gadolinium(III) ion is nine-coordinated by the two oxygen atoms of the salbn moiety, three bidentate nitrate ions and one water molecule. The geometry of GdIII can be described as a square antiprism, in which compound CuII and GdIII are bridged by the two phenolic oxygens of salbn. The CuII–GdIII distance is 3.269(1) Å. The bridging core CuO2Gd is a butterfly shape. Significant distortion was observed for the complex having the larger diamino string. The title compound exhibits seven e.s.r. transitions with |D| = 0.0467 cm–1, which demonstrates the existence of zero field splitting. This outcome indicates that compound (2) consists of a perfectly isolated dinuclear Cu–Gd core and steric bulk alters the dihedral angle in the Cu–O–Gd bridge. 相似文献
45.
P. Hemalatha D. Velmurugan J. Mallika 《Journal of Physics and Chemistry of Solids》2009,70(2):322-1463
X-ray diffraction study of the nonlinear optical (NLO) material S-benzyl isothiouronium chloride (C8H11N2SCl) (SBTC) is reported for the first time. The single crystal of SBTC is orthorhombic with space group Pbca. SBTC exhibits second-order NLO susceptibility, and this study shows that hydrogen bonding is, in part, responsible for this. The present work shows that C-H?Cl and N-H?Cl hydrogen bonds direct the nature of the three-dimensional lattice. Such intermolecular interactions help to extend the molecular charge transfer into the supramolecular realm, the charge transfer originating as a consequence of the high level of molecular planarity and strong donor-to-acceptor interactions. Density functional theory (DFT) calculation and atom-in-molecule (AIM) analysis has been carried out to study the nature of hydrogen involved in the SBTC complex. 相似文献
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49.
Arockiam Anthonysamy Sengottuvelan Balasubramanian Govindasamy Usha Devadasan Velmurugan 《Transition Metal Chemistry》2008,33(6):681-690
The free Schiff bases H2MABCE, H2MABCP, and H2MABCT and their complexes [Ni(MABCE)], [Ni(MABCP)], [Ni(MABCT)], [Cu(MABCE)], [Cu(MABCP)], and [Cu(MABCT)] have been synthesized and characterized by spectroscopic, cyclic voltammetric, and thermal studies. The geometry around nickel is square planar with N2O2 donor atoms. Cyclic voltammetric studies of the Ni(II) complexes show one-electron quasi-reversible waves corresponding to Ni(II)/Ni(I) and Ni(II)/Ni(III) processes. The Cu(II) complexes exhibit an irreversible well defined one electron transfer reduction peak in the range of ?0.34 to ?1.08 V. The electronic spectra of the complexes suggest a four-coordinate geometry. The crystal structure of the ligand H2MABCT and the complex [Ni(MABCP)] have also been reported. The mean Ni–N and Ni–O bond distances are Ni–N = 1.849(4) and Ni–O = 1.837(4) Å. 相似文献
50.
Balaji V. Chandramohan P. Velmurugan S. Ranagarajan S. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):791-801
Journal of Radioanalytical and Nuclear Chemistry - Fission isotopes contribute approximately 10% of the total radioactivity removed from the heat transport circuit of reactor systems during the... 相似文献