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Abstract: The linear-dichroic infrared (IR-LD) spectroscopy of oriented solid samples as suspension in nematic liquid crystal have been carried out for experimental IR-band assignment and structural information of 2-{5,5-dimethyl-3-[2-(2,4,6-trimethoxyphenyl)vinyl]cyclohex-2-enylidene} malononitrile polymorphs. The last data have been compared with known crystallographic ones, thus determining the validity of IR-LD spectral conclusions as well as its possibility to determination of Davydov''s splitting effect and separation of pairs of maxima corresponding to non-equivalent molecules included in the unit cell of given compound. The experimental structural and spectroscopic data in our case are supported with theoretical DFT ones, obtaining both the electronic structure and vibrational frequencies in gas phase. [Copyright &y& Elsevier]

Abstract: 3-Ethylamino-2-(4-nitro-benzoyl)-but-2-enoic acid phenylamide is synthesized, isolated, spectroscopical and structural characterized by means of linear-polarized IR-spectroscopy (IR-LD) of oriented solids as a colloidal suspension in nematic liquid crystal. The experimental IR-band assignment and structural information are supported by quantum chemical calculations at MP2 and B3LYP level of theory and 6-311++G** basis set. The geometry is characterized by two inramolecular hydrogen bonds of NH…Ond lengths of 2.589 and 3.449Å. The NHO angles are 142.1(3)° and 125.8(4)°, respectively. A transoide configuration of amide fragments is predicted with a torsion NH–Cf 150.6°. Phenyl fragments are mutually perpendicular oriented closing an angle of 92.6°. [Copyright &y& Elsevier]

1,1,1-Trichloro-3-(1-phenethylamino-ethylidene)-pentane-2,4-dione is spectroscopically and structurally elucidated by means of linear-polarized IR spectroscopy (IR-LD) of oriented solids as a colloidal suspension in nematic liquid crystal. Structural information and IR-spectroscopic assignment are supported by quantum chemical calculations at MP2 and B3LYP level of theory and 6-311++G** basis set. The geometry is characterized with an inramolecular hydrogen bond of NH...O&dbond;C with length of 2.526 Å and a NHO angle of 140.5(1)°. The NH&bond;C(CH3)C&dbond;C&bond;C&dbond;O(CH3) fragment is nearly flat with a maximal deviation of total planarity of 10.4°. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: By means of IR-LD spectroscopy of oriented as suspension in nematic liquid crystal solids, a detailed IR-bands assignment and a stereo-structural prediction of codeine, codeinone and N-norcodeine have been carried out. The data are compared with known crystallographic ones of codeine and codeinone obtained by single crystal X-ray diffraction. [Copyright &y& Elsevier]

Abstract: Methioninamide ester amide of squaric acid ( 1 ) has been analyzed structurally and IR-spectroscopically by means of ab initio calculations and solid-state linear-polarized IR-spectroscopy (IR-LD) of oriented solid-samples as suspension in nematic liquid crystal. The obtained data are compared with known single crystal X-ray diffraction ones. The experimental IR-spectroscopic bands assignment in solid-state has been reported as well, using reducing-difference procedure for polarized IR-spectra interpretation. [Copyright &y& Elsevier]

Abstract: The possibilities of IR-LD spectroscopy of oriented solid samples as nematic liquid crystal suspension are used for detailed IR-band assignment of l-tyrosinamide hydrochloride monohydrate. In addition the theoretical ab initio results of protonated l-tyrosinamide on UHF/6-31++G∗∗ in gas phase are presented. [Copyright &y& Elsevier]

The structure of a mononuclear Au(III) complex of the dipeptide glycyl-S-serine (Gly-Ser) has been predicted using solid-state linear dichroic IR (IR-LD) spectroscopy, based on an orientation technique in a nematic liquid crystal suspension. Results are compared with data from 1H- and 13C-NMR, MS, elemental analysis, thermogravimetry and differential scanning calorimetry. The metal ion is coordinated as a tridentate through NH2, N (from deprotonated amide) and O (COO-) groups to form [Au(C5H9N2O4)Cl], with the fourth position of the square-planar coordination sphere being completed by a Cl- ion. [ABSTRACT FROM AUTHOR]

Abstract: IR-LD spectroscopy of oriented solid-samples as a suspension in nematic liquid crystal has been applied for IR-characteristic bands assignment of 6-acetylcodeine and its hydrogensquarate. A stereo-structural prediction of both compounds has been shown as well, comparing with known single crystal X-ray diffraction results of 6-acetylcodeine. [Copyright &y& Elsevier]