Transition from Static to Dynamic Jahn-Teller Effects as Exhibited by the EPR Spectra ofAg2+in SrO, CaO, and MgO

EPR investigations of ${\mathrm{Ag}}^{2+}$ in the series of isomorphous hosts SrO, CaO, and MgO show that the low-temperature Jahn-Teller effect is static for SrO: ${\mathrm{Ag}}^{2+}$, predominantly static but intermediate to the dynamic effect for CaO: ${\mathrm{Ag}}^{2+}$, and predominantly dynamic but slightly intermediate to a static effect for MgO: ${\mathrm{Ag}}^{2+}$. This represents the first observation of the systematic transition from static to dynamic Jahn-Teller effects at low temperature.