Theoretical study on the sandwich clusters of Nan(COT)m by density functional method

Geometry optimization of Na-n(C8H8)(m) (Na-n(COT)(m) - 1,3,5,7 cyclooctatetraene, COT) cluster is carried out at the level of VWN employing generalized gradient approximations considering exchange-correlation correction. Geometry structures, total bonding energies, emission wavelengths as well as Mulliken atomic net populations are obtained. A stable geometry with a higher point symmetry is found for Na-n(COT)(m) cluster. The theoretical results of bond lengths of C-C and C-H in Na-n(COT)(m) cluster are in good agreement with the limited theoretical results. Our theoretical results of Mulliken atomic populations indicate that C8H8(COT) interacts with Na mainly by p-pi, the electrons transfer from Na to C8H8 and the interaction of Na and COT forms stable complexes. (C) 2000 Elsevier Science B.V. All rights reserved.