Colour centers in strontium chloride

X irradiation of SrCl2 at 77 K produces VK centres and F centres; H centres are not produced in observable concentration. A study of the effects of polarized bleaching light on the optical and EPR spectra shows that a 2 Sigma -2 Sigma type transition of the VK centres occurs at 397 nm. The VK centres decay at 105 K with an activation energy of 0.251 eV. Some of the moving holes are trapped at lattice defect sites forming VKA centres. Only perturbed F centres are observed in appreciable concentration in the irradiated crystals. These centres have been investigated by EPR and magneto-optical methods. The F band shows partly resolved structure with peaks at 580 and 667 nm.