We aim to investigate the vibrational dynamics of frozen solutions of alkalides (K+ Na-) comprising the fully methylated aza-crown hexamethyl hexacyclen (HMHC). This proposal has grown out of our recent TOSCA XPress measurements in which we successfully demonstrated the ability of INS to study alkalide/complexant-solvent interactions. It will provide complementary data to our liquid structure studies, and will shed light on the dynamics of stable alkalides in solution for the first time.