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Glass materials on basic GeO2 are of interest in connection with the increasing interest in glass as the new materials for optics and fiber optics [1]. Glass former-activator and crystal-activator compositions are of considerable interest for elucidating the structure and bonding in vitreous (isotopic) and crystalline (anisotropic) systems. Information about the behavior of the activator in these materials can be obtained from electron-spin response (ESR) signals.