Expanded fullerides and electron localisation – lithium-rich ammoniated C60 phases

Abstract

The synthesis and characterisation of alkali metal fullerides with complex counterions consisting of ammonia ligands coordinated to lithium cations is discussed. The body-centred cubic packing and accompanying low density of fulleride anions produces localisation of the t_1u outer electrons of the fulleride anions. This is demonstrated by the electronic behaviour of the x = 3 and 5 members of the series, the latter representing the first detailed study of the electronic behaviour of a localised electron fulleride with five electrons per anion.