title: Structure, vibrational spectra and DFT characterization of the intra- and inter-molecular interactions in 2-hydroxy-5-methylpyridine-3-carboxylic acid--normal modes of the eight-membered HB ring.
abstract: Fourier transform IR and Raman spectra, XRD studies and DFT quantum chemical calculations have been used to characterize the structural and vibrational properties of 2-hydroxy-5-methylpyridine-3-carboxylic acid. In the unit-cell of this compound two molecules related by the inversion center interact via OH⋯N hydrogen bonds. The double hydrogen bridge system is spaced parallel to the (102) crystallographic plane forming eight-membered arrangement characteristic for pyridine derivatives. The six-membered ring is the second characteristic unit formed via the intramolecular OH⋯O hydrogen bond. The geometry optimization of the monomer and dimer have been performed applying the Gaussian03 program package. All calculations were performed in the B3LYP/6-31G(d,p) basis set using the XRD data as input parameters. The relation between the molecular and crystal structures has been discussed in terms of the hydrogen bonds formed in the unit cell. The vibrations of the dimer have been discussed in terms of the resonance inside the system built of five rings coupled via hydrogen bonds.
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland. Electronic address: patrycja.godlewska@ue.wroc.pl.
authors.forename: P
authors.initials: P
authors.lastname: Godlewska
authors.affiliation: Department of Solid State Spectroscopy, Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Jańczak
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland.
authors.forename: E
authors.initials: E
authors.lastname: Kucharska
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland; Department of Solid State Spectroscopy, Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Hanuza
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Lorenc
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Michalski
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland.
authors.forename: L
authors.initials: L
authors.lastname: Dymińska
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economy, University of Economics, 118/120 Komandorska Str., 53 - 345 Wrocław, Poland.
authors.forename: Z
authors.initials: Z
authors.lastname: Węgliński
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019281:Dimerization; D006860:Hydrogen Bonding; D008745:Methylation; D008958:Models, Molecular; D011725:Pyridines / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D002264:Carboxylic Acids; D011725:Pyridines
keywords: DFT; Dimer; HB ring; Hydrogen bridge; Vibrational spectra; X-ray