title: X-ray, vibrational and theoretical studies of weak hydrogen bonds in bis(4-nitroanilinium) hexachloridostannate.
abstract: Crystal structure of bis(4-nitroanilinium) hexachloridostannate, (H4NA)2SnCl6, was determined by means of X-ray single crystal diffraction. In the crystal structure, weak N-H…Cl hydrogen bonds are present. These interactions were taken into consideration in calculations of vibrational spectra for the [(H4NA)Cl4O](5-) anion. Very good agreement between theoretical and experimental frequencies was achieved. The calculations were done at the B3LYP/6-311+G(2d,1p) level including Grimme's correction for dispersion. The relaxed potential energy surface indicated that the energy of H4NA(+) ion is approximately independent upon rotation of the ammonio group. The energy barrier is 0.01 kcal/mol. Therefore the position of the ammonio group can be easily modified the other interacting molecules during molecular self-assembly and crystal growth processes. The energy of the H4NA(+) ion significantly depends on the relative position of the nitro group towards the aromatic ring. The energy barrier of the nitro group is 4.35 kcal/mol.
authors.affiliation: Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna Str. 2, P.O. Box 1410, 50-950 Wrocław, Poland. Electronic address: m.daszkiewicz@int.pan.wroc.pl.
authors.forename: Marek
authors.initials: M
authors.lastname: Daszkiewicz
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D007477:Ions; D008958:Models, Molecular; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013816:Thermodynamics; D017971:Tin Compounds / Q000737:chemistry*; D014732:Vibration
chemical_list: D000814:Aniline Compounds; D007477:Ions; D017971:Tin Compounds; C019498:4-nitroaniline; C023650:aniline
keywords: 4-Nitroaniline; Crystal structure; Elementary graph-set descriptors; Hexachloridostannate; PED analysis; Theoretical spectra