The alternating-current conductivity of solid solutions which contained mole fractions, of CsI or KI, of up to 0.13 was measured. The high-conductivity -phase of TlI was retained to room temperature by incorporating 7.5mol% of CsI. No such effect was observed upon adding up to 13mol% of KI. The -phase stabilization was explained in terms of a stronger bonding between Cs+ and I- than between Tl+ and I-.

E.A.Secco, A.Sharma: Journal of the Physics and Chemistry of Solids, 1995, 56[2], 251-4