Electron Spin Resonance Study of Centers Formed in γ-Irradiated PbCl2 Crystals

Abstract

An analisis is presented by utilizing the electron spin resonance spectra of new defects which are produced in PbCl₂ single crystals irradiated at liquid nitrogen temperatures with γ-rays from a ⁶⁰Co source. One of the g tensor axes of the defects corresponds to the crystallographic c-axis, and the other two make an angle of about 12° with the a- and b-axes. The components of the g-factor are g _x =1.494±0.005, g _y =1.322±0.005 and g _z =1.662±0.005. The principal axes of the hyperfine coupling tensor A are collinear with neither the g tensor axes nor the crystallographic axes. The resolved hyperfine structure indicates that these defects fit a model of the paramagnetic centers consisting essentially of an electron trapped at paired lead ions, that is, the Pb₂ ³⁺ centers.