Chromium-doped CdF2 crystals by ESR spectroscopy

Single crystals of Cr-doped CdF₂ in which only Cr²⁺ ions were present were obtained by heating CdF₂:CrF₃ samples in Cd vapors. The crystals produced were studied by ESR spectroscopy at X band at 4.2 ^oK. The spectrum obtained is described by the effective spin Hamiltonian:

g⁽²⁾_eff = 4g_zcosΘ, g⁽¹⁾_eff = 2g_zcosΘ, where i = 1 for the doublet of the spin S = 1, and i = 2 for the doublet of the spin S = 2; net effective spin $\text{S}\text{=}\text{1}\text{2}$; g_z=1.85±0.03; |Δ₍₂₎|=3.08±0.07 GHz; |Δ₍₁₎|=5.85±0.07 GHz; $\text{1}\text{6}\text{(Δ}{}^{\mathrm{o}}{}_{\mathrm{(2)}}\text{? Δ}{}^{\mathrm{o}}{}_{\mathrm{(1)}}\text{)=?11.01±0.02}\text{GHz}$.