Hypersensitive transitions of Tm3+, Ho3+ and Dy3+ rare-earth ions in garnet crystals

► The intensities of transitions of Tm3+, Ho3+, Dy3+ ions in garnet crystals were determined. ► The hypersensitive transitions of these ions in Ca3(NbGa)5O12 are characterized by high values of intensity. ► This fact is explained by presence of rare earth ions with local symmetry C2, C2v, C1 in Ca3(NbGa)5O12 crystals.