A stochastic relaxation model for the Mössbauer spectra of ferric oxide spin glasses was used to analyze the spectra for the mixed spinel ${\mathrm{Mg}}_{1+\mathit{t}}$${\mathrm{Fe}}_{2\mathrm{-}2\mathit{t}}$${\mathrm{Ti}}_{\mathit{t}}$${\mathrm{O}}_4$ with composition t=0.70. The results compare favorably with previously published results on the system ${\mathrm{BaSn}}_{\mathit{x}}$${\mathrm{Ti}}_{2\mathrm{-}\mathit{x}}$${\mathrm{Fe}}_4$${\mathrm{O}}_{11}$ with compositions x=0.40 and x=0.80, and suggest empirical scaling laws for the spin-order parameter defined as q=〈${\mathit{S}}_{\mathit{z}}$〉/S and the spin correlation time ${\mathrm{\tau }}_{\mathit{c}}$ in these ferric oxide spin glasses. It was found that the quantity ${\mathrm{\tau }}_{\mathit{c}}$${\mathit{T}}_{\mathit{G}}$ versus T/${\mathit{T}}_{\mathit{G}}$ follows a scaling curve with approximately a power-law dependence below the glass temperature. The order parameter follows a scaling curve q=1-(T/${\mathit{T}}_{\mathit{G}}$${)}^{\mathrm{\beta }}$, with a value β=2.48±0.19.

• Received 6 December 1994

DOI:https://doi.org/10.1103/PhysRevB.51.15581