NEW MIXED-TYPE ROTATIONAL CRYSTALLINE STATE OF SOLIDS ON AN EXAMPLE OF PARAFFIN

The detailed X-ray diffraction study of normal paraffins in the C22H46 -C24H50 system at various temperatures was performed at a temperature step of several tenths of degree. The obtained experimental results in dicate the existence of a new type of the rotational crystalline state of solids intermediate between low- and high-temperature types. In th e case of paraffins, this state is characteristic of solid solutions a nd corresponds to a mixed-type thermal motion of chain molecules withi n the same structure: a combination of chaotic torsional vibrations (l ow-temperature type) and full rotations (high-temperature type) about the chain axis.