论文信息 - ESR of thermoluminescent centres in CaSO4 single crystals

ESR of thermoluminescent centres in CaSO4 single crystals

ESR measurements on X-irradiated undoped CaSO4 single crystals at 77K reveal two related radiation damage centres. Step annealing measurements suggest a connection between these centres and the thermoluminescent glow peaks at approximately 395 and 465K. An analysis of the g-values (centre I: gx=2.006, gy=2.0091 and gz=2.0395; centre II; gx=2.0011, gy=2.0084 and gz=2.0256) in conjunction with the known crystal structure indicates that the defects could result from the removal of an electron from a non-bonding orbital of a sulphate oxygen atom adjacent to a Ca2+ vacancy. The ESR signals related to these centres exhibit an unusual dependence on temperature and microwave power between 120 and 250K, which is attributed to a motional transition.

J. Pilbrow | R. J. Danby | J. F. Boas | R. Calvert

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