Un nouveau conducteur protonique [H(H 2O) n] 12Sb 12O 36 (n ⩽ 1)

Abstract

Single crystals of K 14Sb 12O 36F 2 undergo rapid ion exchange in 9N sulfuric acid to produce “hydronium” compound (H(H 2O) n) 12Sb 12O 36 (n ⩽ 1). Between 30 and 140°C this phase undergoes a partial and reversible dehydratation in which approximately 85 % of its “H 3O +” content is converted to H +. The structures of hydrated and dehydrated phases have been refined by full-matrix least squares, respectively to factor R = 0.030 and 0.047. The conductivity of (H(H 2O) n ) 12Sb 12O 36 (σ 20 ⋍ 1O 7 Ω −1cm −1 ) increases in an Arrhenius relationship with an activation energy of 8.8 kcal.mole −1, the dehydrated compound (H(H 2O) 0.33) 12Sb 12O 36 has a much lower conductivity but the same activation energy.