Three components organic superconductors: Intercalation of KH into C-60

We have prepared (KH)(3)C-60 as an initial composition by direct reaction o f potassium hydride (KH) to C-60. (KH)(3)C-60 had higher T-c(19.5 K) and la rger lattice constant (14.351 Angstrom) compared with K3C60 prepared by dop ing of potassium metal. The expanded lattice constant is suggestive of the intercalation of hydrogen. The evidence of the inclusion of hydrogen was gi ven by mass-analyzed thermal desorption experiment. We have also prepared ( NaH)(4-x)(KH)(x)C-60 to study the substitutional effect of KH to (NaH)(4)C- 60. It was found that the superconducting phase is stabilized by substituti on of only a few percent KH as seen in (NaH)(3.9)(KH)(0.1)C-60. (C) 1999 Ac ademic Press.