Magneto-optical study of 4T1 state of Mn2+ in ZnS

An experimental magneto-optical study of the relaxed excited 4T1 level of Mn2+ in ZnS is reported. A strong Jahn-Teller interaction model involving an E-mode is able to explain the positions and intensities of zero-phonon lines in the excitation spectrum versus magnetic field and the magnetically induced circular polarisation. The relaxed excited state was found to be non-resonant and this explains past and present failures to detect EPR optically.