Density of states singularities in K xC 60 probed by electron spin resonance

Abstract

The ESR measurements performed on superconducting K x C 60 are interpreted in terms of transitions within states bound to C 60 molecules. The effective g factor varies with x in the compounds. It is understood as the influence of the distortion of the highly symmetrical cations field on the carriers bound to charge C 60 molecules. In the compound with all interstices occupied the symmetry is restored and single ESR line position corresponds to g=≈ 2.0023.