EPR of V centres in plastically deformed CaS

V centres in plastically deformed SrS

“…These defects increase in number due to transformation of isolated cation vacancies into some complexes by ionic processes on annealing. Similar defects have been observed previously in plastically deformed CaS [11]. Moreover, the total scene was very analogous in CaS and SrS: the EPR spectra were very similar in both cases, with the only scale difference of magnetic fields; also, only the scale difference of temperatures exists in thermal stability of defects in SrS and CaS when electron-hole or ionic processes are studied.…”

“…The value obtained is very close to the g-factor of a free electron and to the values obtained for V centres in AEO [14] and CaS [11]. The variation in g k value is very small for different types of V centres.…”

“…The EPR spectra of V centres are very similar in such A II B VI materials as AEO (alkaline earth oxides, e.g. [10]) and AES (CaS [11] and SrS). The models of observed defects were first established in [11] for plastically deformed CaS.…”

“…Thus, to estimate the values of g k , we make use of the formula connecting the averaged g-tensor value for V À centres with g ? and g k values [11] (see below).…”

“…[10]) and AES (CaS [11] and SrS). The models of observed defects were first established in [11] for plastically deformed CaS. We summarize below the most essential features of V centres before we start the discussion of data obtained recently in SrS: a) the EPR spectra demonstrate an axial symmetry of the g-tensor, where g k % 2:00 and g ?…”