The determination of molecular structure of 1,3,5-trichlorobenzene from X-ray diffraction study

Abstract

The paper reports results of the X-ray diffraction structural studies of liquid 1,3,5-trichlorobenzene, at 358K, with the use of MoKα radiation of the wavelength λ=0.71069Å. The observable range of scattering angles was 6°≤2Θ≤120°. The function of reduced radiation intensity was analysed by the reduction method of Blum and Narten. Also for the first time the method of reduction proposed by Mozzi–Warren has been applied to verify the assumed model of the molecule studied and to separate the intra- from intermolecular interactions. Experimental distributions of X-ray scattered intensity were compared with theoretical results predicted by the proposed model of 1,3,5-trichlorobenzene molecule. A good agreement between the theoretical im(S) and experimental functions i(S)=[Ieu(S)/N−∑ucfj2(S)]/g2(S), was obtained on assuming the statistically most probable model of the molecule studied. Mean amplitudes of vibrations 〈uij〉 as a function of CC internuclear distances in 1,3,5-trichlorobenzene molecule were calculated. Analysis of intramolecular interactions between pairs of atoms has been made, taking into account the values of the temperature factors exp[−(〈uij〉/2)S2]. The structural data obtained by X-ray analysis for liquid were discussed. Conclusions concerning the most correct interpretation of experimental data are pointed out.