Interaction and superconducting transition in alkali‐doped C 60

The intermolecular interactions in alkali‐doped C 60 solids, A 3‐x‐y A′ x A″ y C 60 (A, A′, A″ = alkali; x + y ⩽ 3), have been calculated, and their correlations with the structures and the superconducting transition temperatures T c have also been investigated. It is found that the variations of the lattice constants a 0 of A 3‐x‐ y A′ x A″ y C 60 solids and the superconducting transition temperatures T c can be satisfactorily explained from the viewpoint of interaction. It is shown that the relationship of T c with interaction is much closer than that of T c with lattice constant a 0 , Therefore, we can say it is the physical factors such as interaction, other than the geometrical structure factors such as a 0 , that should be reasonably taken as the primitive cause of the sudden change of superconductivity from pristine C 60 to its alkali‐doped compounds and of the variation of T c among superconductors of A 3‐x‐y A′ x A″ y C 60