Electron spin resonance of Mn2+ in sodalite

Electron spin resonance of allowed (Δm=0) and forbidden (Δm=±1) hyperfine transitions of Mn²⁺ in sodalite, Na₈(Al₆Si₆O₂₄)Cl₂, is reported. No fine structure other than the central M=∣+1/2>?∣?1/2> transition is observed. From intensity ratios of forbidden to allowed transitions and doubling of allowed lines in powder spectra the crystal field parameter |D| was estimated as equal to (8±5) 10^?3 cm^?1. The g-value for the spectrum was obtained as equal to 2.0033±0.0005. The hyperfine structure constant |A| was 83±1 gauss, equal to (77±1) 10^?4 cm^?1.