Permutation-Inversion Group of Fullerite C70 in the Intermediate Phase

Abstract

The permutation-inversion symmetry group of fullerite C 70 in the intermediate phase (at temperatures 270 K < T < 340 K) and the permutation-inversion site symmetry group of a rotating molecule C 70 in a nonrigid crystal are generated. Their irreducible representations compatible with the principle of symmetry of wave functions with respect to the permutations of identical nuclei are found. Group theoretical classification of quantum-mechanical states of a rotating molecule and a crystal in the intermediate phase of fullerite C70 is made. The selection rules for electronic and IR spectra in terms of the irreducible representations of the permutation-inversion group are found.