Density functional study on geometry and electronic structure of Eu@C-60

We investigate the geometry and the electronic structure of Eu@C-60 by the scalar relativistic full-potential linear-combination-of-atomic-orbitals me thod based on the density functional theory within the local-spin-density a pproximation. It is found that the reaction Eu + C-60 --> Eu@C-60 is exothe rmic with the reaction energy of about - 3 eV. Eu is placed at about 1.2 An gstrom awav from the center of the C-60 cage. Two 6s electrons in Eu are tr ansferred to the lowest-unoccupied-molecular orbitals of C-60 while seven 4 f electrons remain in Eu. The Eu atom in Eu@C-60 thus exists as Eu2+. (C) 2 000 Published by Elsevier Science B.V.