Showing papers by "Susumu Saito published in 1991"

Ionic metal KxC60: Cohesion and energy bands.

Abstract: Microscopic total-energy electronic-structure calculations for K{sub {ital x}}C{sub 60} show that solid C{sub 60} weakly bonded via van der Waals forces is transformed upon potassium doping into a strongly condensed {ital ionic} {ital metal} in which both Madelung and kinetic energies contribute to its large cohesive energy and bulk modulus. We also find that K doping induces lattice contraction which results in nonrigid energy-band modification. The Fermi level for K{sub 3}C{sub 60} is found to be located close to a peak of the density of states.

Fermi surfaces of alkali-metal-doped C60 solid

Abstract: We present the first-principles electronic-structure calculation which provides outstanding features in the Fermi surface of KxC60. We have found that there exist two main Fermi surfaces: One is a hole pocket around the center of the Brillouin zone, and the other a large hole surface extending to the zone boundary. We have also found Fermi-surface nesting resulting in a peak at q=(1, 0, 0)2π/a in the susceptibility χ(q), which may induce an instability in this exotic material.