Enhanced Luminescence in the Layered Single Crystal Ce[Ag(CN)$_2$]$_3$

Single crystals of the form Ln[M(CN)$_2$]$_3$ (Ln=trivalent rare earth; M=Ag, Au, or both) have a layered structure consisting of alternating layers of M(CN)$_2^-$ ions and Ln$^{3+}$ ions. Recent work on this type of crystal has focused on energy transfer from the metal dicyanide donor to the rare earth acceptors, specifically Tb$^{3+}$, Eu$^{3+}$, and Sm$^{3+}$. Crystals of Ln[Ag(CN)$_2$]$_3$ are particularly interesting because they exhibit site-selective excitation. However, the luminescence intensity in these crystals is vanishingly weak at ambient temperatures. We present preliminary luminescence results from a new sample, Ce[Ag(CN)$_2$]$_3$. This crystal displays strong luminesence at all temperatures between 78 K and 295 K, in contrast with all other rare earth dicyanoargentates we have studied. We present steady-state excitation and emission results along with time-resolved measurements of both the cerium doped crystal and the single crystal La[Ag(CN)$_2$]$_3$ for comparison.