Fourier analysis of the durene structure

In recent paper the crystal structure of durene, 1. 2. 4. 5. -tetramethyl benzene, has been described. The experimental work, including the measurement of the X-ray intensities, has been dealt with, and the structure deduced to within fairly narrow limits by trial and error methods. In order to obtain more precise information about the orientation and molecular structure of this benzene derivative, a double Fourier analysis has now been applied to the structure factors for the three principal crystallographic zones, and the results are set out below. Crystal Data. Durene.—C10H14. Melting point 80° C. Density 1⋅03. Monoclinic prismatic. a = 11⋅57,b = 5⋅77, c = 7⋅03 A., β = 113⋅3°. Space group C2h5 (P21/a). Two molecules per unit cell. Molecular symmetry, centre. Molecular volume, 430 A3. Total number of electrons per unit cell = F(000) = 148.