Linewidths of Paraelectric-Resonance Transitions

Calculations are given for the linewidths of the paraelectric resonance transitions of O${\mathrm{H}}^{-}$ ions introduced as impurities in KCl. The methods are applied to the transitions reported by Feher, Shephard, and Shore. The width of the narrow line of this experiment is caused both by the dipole-dipole interaction and by strains, presumably arising from dislocations. The broad line observed is primarily strain-broadened.