The effect of methyl hydrogens on the librational motion of naphthalene molecules in a durene host crystal

We have studied the properties of naphthalene molecules in a durene host crystal by means of a computer calculation of the intermolecular interactions. The amazingly large reorientation of the naphthalene molecule upon absorption of a (pseudo-) localized phonon in its photoexcited triplet state appears to be caused by the motion of the methyl groups of neighbouring durene molecules. © 1983.