A study of the natural α-recoil damage in zircon by infrared spectra

Natural α-recoil damage of 30 natural zircon specimens from Ceylon have been examined by studying the infrared absorption spectra from 1 to 15 μm. Two synthetic zircon specimens were also studied as undamaged reference specimens. The ir absorption coefficient at 6 μm (1666 cm −1 ) was found to be a function of radiation damage. The ir data can be explained by a dual damage mechanism. The initial damage process produces degradation of the v 3 vibrational mode in the ir spectra which can be explained by deformation of SiO 4 tetrahedra, whereas the predominant effect of the advanced stage of radiation damage is the breakdown of the zircon lattice into SiO 2 and ZrO 2 which causes a skewing of the v 3 absorption band. These data substantiate the model of Pellas and clarify the dualistic nature of the radiation damage mechanism.