The interpretation of vibrational spectra is often complex but a detailed knowledge of the normal modes responsible for the experimental bands provides valuable information about the molecular structure of the sample. In this work we record and assign in detail the infrared (IR) spectrum of the benzylic amide [2]catenane, a complex molecular solid displaying crimped mechanical bonds like the links of a chain. In spite of the large size of the unit cell, we calculate all the vibrational modes of the catenane crystal using quantum first-principles calculations.
View Article and Find Full Text PDFVibrational band shape analysis through time correlation function concept is widely used to obtain experimental information on the molecular dynamics of medium-size molecules in different environments. Interesting details are revealed by extending this technique to biomolecules such as functional groups of the nucleic acids in media approaching the physiological conditions. In this work a study into the UV resonance Raman (UVRR) vibrational half bandwidths of functional groups in LacDNA, upon lowering the pH (pH 6.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
October 2008
Inclusion complexes of atenolol with beta-cyclodextrin (beta-CD) in aqueous solution have been investigated with 1H NMR and UV-vis spectroscopy. The stoichiometry of this inclusion complex was established to be equimolar (1:1) and its stability constant was determined by UV-vis spectroscopy. The crystal structure of the beta-CD-atenolol (1:1) inclusion compound has been solved from synchrotron powder diffraction data using direct-space search techniques.
View Article and Find Full Text PDF9-beta-D-arabinofuranosyaldenine-5'-monophosphate (5'-ara-AMP) is an arabinonucleotide that has antiviral and antitumor activity. The accurate knowledge of the nature of its vibrational modes is a valuable step for the forthcoming elucidation of drug-nucleotide and drug-enzyme interactions. The FTIR and FT Raman spectra (4000-30 cm(-1)) of 5'ara-AMP and two deuterated derivatives ara-AMP-d(C8) (deuteration in C8) and ara-AMP-d7 (deuteration in C8, amino and hydroxyl groups) are reported.
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