The structure and dynamics of solid benzene. I: A neutron powder diffraction study of deuterated benzene from 4 K to the melting point

The crystal structure of deuterated benzene has been investigated over the complete temperature range 4–280 K. Our results are in excellent agreement with previous studies, recorded at a limited number of temperatures, and display a smooth variation of the lattice parameters over the complete temperature range. No evidence of the suggested low‐temperature phase transitions, or marked premelting effects have been found. Detailed measurements of the lattice parameters close to the melting point display an anomalous behavior of the b lattice parameter and the orientation of the molecules which is believed to be evidence of a disordering transition at temperatures above the melting point.