Optically-Detected Magnetic Resonance Of Molecular Color Centers Co3- And No3 In Gamma-Irradiated Beryl

In this paper we identify, with optically-detected magnetic resonance via the magnetic circular dichroism of the absorption, the NO3 and CO3 molecular radicals trapped in the structural channels of gamma-irradiated beryl. We confirm that, along with the CO3-, the NO3 is also responsible for the blue color by introducing several absorption peaks between 14500 cm(-1) and 18000 cm(-1) (720 mn down to 540 nm). Their individual contributions to the overall many-peak optical spectra have been established and most of the transitions could be explained in terms of a combination of crystal-field and spin-orbit split (2)A(2)' -> E-2' transition plus vibronic replicas. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.