SPECTROSCOPIC CHARACTERIZATION AND ROOM-TEMPERATURE STRUCTURE OF BIS(4-AMINOPYRIDINIUM) DICHROMATE
R. Ben Smail1,2, H. Chebbi3,2, B.R. Srinivasan4, M.F. Zid2
1University of Carthage, Nabeul, Tunisia 2University of Tunis El Manar, Tunis, Tunisia 3University of Tunis, Montfleury, Tunis, Tunisia chebhamouda@yahoo.fr 4Goa University, Goa, India
Ключевые слова: crystal structure, infrared spectroscopy, bis(4-aminopyridinium) dichromate
Страницы: 757-765
Аннотация
Crystals of bis(4-aminopyridinium) dichromate (C5H7N2)2[Cr2O7] (1) were isolated via slow solvent evaporation and characterized by energy dispersive spectroscopy (EDS), infrared (IR) and ultratviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction. The room-temperature (RT; 298 K) phase of 1 crystallizes in the monoclinic space group P21/m. Its asymmetric unit consists of two crystallographically independent 4-aminopyridinium cations (A and B) and two halves of symmetry-independent dichromate anions (A and B). Cations and anions are linked with the aid of several moderate N-H⋯O hydrogen bonds and weak C-H⋯O interactions resulting in a three-dimensional supramolecular network. The crystal structure is further stabilized by extensive p-p stacking interactions between adjacent pyridine rings. A comparison of the structure of the RT phase of 1 and that of the low temperature (LT; 150 K) phase is described.
DOI: 10.15372/JSC20170412 |