OFF-AXIS EXTRA LINES IN POWDER PATTERN ELECTRON-PARAMAGNETIC-RESONANCE OF CR3+ IN YALO3

Powder sample electron paramagnetic resonance (EPR) spectrum of Cr3+ i ons in YAlO3 crystals contains off-axis extra lines, which do not belo ng to the principal X, Y, and Z components of the fine structure. Orie ntation dependence of the EPR spectrum of Cr3+ doped YAlO3 single crys tal confirms the existence of extra turning points corresponding to di rections lying off the X, Y, and Z axes, consistent with theoretical p redictions. This results in five EPR lines due to the transition betwe en the central Kramers doublet in the powder system. The observed powd er pattern EPR has been used in identification of Cr3+ as an impurity ion in undoped YAlO3 crystals. (C) 1997 American Institute of Physics.