Structure et spectroscopie (IR, Raman et neutron) des molécules aromatiques encagées dans des dérivés de triazines

Abstract

Our thesis was dedicated to systematically extend recent observations indicating that the molecular conformation and certain modes of vibration of the 4,6-dichloro-5-methylpyrimidine (4,6dC5MP), 3,5-dibromo-4- methylpyridine (3,5dB4MPn) and 2,4,6-Collidine encaged in the BrPOT from X-ray diffraction at ambient temperature. Hirschfield’s surface analysis is generated through the Crystal Explorer program, providing information on the existing interactions in the structure of both products and helping to view and understand its crystalline stack. In parallel to the experimental study, we made theoretical calculations of the conformation of the single molecule using the methods of the DFT (Density Functional Theory) well known for their precision and normal modes of vibration. The results of calculation of quantum mechanics made by (DFT) with the functional MPW1PW91 and Lanl2DZ base led to similar results in the angles and bond lengths in relation to the experiment. The theoretical calculations of spectroscopy allowed the identification of the different modes of vibration of the molecule. The inelastic neutron scattering (INS) technique was used to study the tunneling effect of the methyl group of collidine encaged, and tunnel burstings were measured. These values correspond to the generator potential.