title: Comprehensive physicochemical studies of a new hybrid material: 2-amino-4-methyl-3-nitropyridinium hydrogen oxalate.
abstract: A new organic-organic salt, 2-amino-4-methyl-3-nitropyridinium hydrogen oxalate (AMNPO), and its deuterium analogue have been synthesized and characterized by means of FT-IR, FT-Raman, DSC and single crystal X-ray studies. The DSC measurements and temperature dependence of the IR and Raman spectra in the range 4-295 K show that it undergoes a reversible phase transition at ~240 K. At room temperature it crystallizes in noncentrosymmetric space group P21. The unit-cell is built of the 2-amino-4-methyl-3-nitropyridinium cations and oxalate monoanions which are connected via the N-H···O and O-H···O hydrogen bonds. The geometrical and hydrogen bond parameters are similar for non-deuterated (at 120 and 293 K) and deuterated compounds (at 90K). The phase transition is probably a consequence of order-disorder transition inside of hydrogen network. The 6-311G(2d,2p) basis set with B3LYP functional have been used to discuss the structure and vibrational spectra of the studied compound.
authors.affiliation: Department of Bioorganic Chemistry, Institute of Chemistry and Food Technology, Faculty of Engineering and Economics, Wrocław University of Economics, 118/120 Komandorska, 53-345 Wrocław, Poland. Electronic address: isai@o2.pl.
authors.forename: I
authors.initials: I
authors.lastname: Bryndal
authors.forename: E
authors.initials: E
authors.lastname: Kucharska
authors.forename: M
authors.initials: M
authors.lastname: Wandas
authors.forename: J
authors.initials: J
authors.lastname: Lorenc
authors.forename: K
authors.initials: K
authors.lastname: Hermanowicz
authors.forename: M
authors.initials: M
authors.lastname: Mączka
authors.forename: T
authors.initials: T
authors.lastname: Lis
authors.forename: M
authors.initials: M
authors.lastname: Marchewka
authors.forename: J
authors.initials: J
authors.lastname: Hanuza
mesh_terms: D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D010070:Oxalates / Q000737:chemistry*; D011726:Pyridinium Compounds / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014732:Vibration; D014961:X-Ray Diffraction
chemical_list: C000589107:2-amino-4-methyl-3-nitropyridinium hydrogen oxalate; D010070:Oxalates; D011726:Pyridinium Compounds
keywords: 2-Amino-4-methyl-3-nitropyridinium hydrogen oxalate; Crystal structure; Deuterated salt; IR and Raman spectra; Temperature dependence