Electron Paramagnetic Resonance of Mn²⁺ at the Three Sites of Yttrium Aluminium Garnet

Abstract

Abstract Electron paramagnetic resonance measurements have been made at 17.4 GHz at room and liquid helium temperatures of divalent manganese substituted into the three sites of yttrium aluminium garnet (YAlG). The relative intensities of the tetrahedral, octahedral, and dodecahedral spectra were respectively 3:2:30. Data at liquid helium temperatures in units of 10 −4 cm −1 are for tetrahedral site: g z = 2.001, B = −170.6, B = 0.062, A z = −69.1; for octahedral site: g z = 2.001, B = −139.3, B = −0.088, A z = −82.3; for dodecahedral site: g z = g y = 2.001, B = −102.2, B 2 2 = −167.8, B = −0.006, ( B + B ) = 0.11, A z = −85.1, A y = −85.9. The second order zero field splittings were compared to the various existing crystal field models using the local crystalline fields at the three sites obtained by summing up the contributions of the point monopoles to convergence. Poor agreement was obtained.