We report the geometrical structure, vibrational, and excitation spectra of novel, fullerene-analog C-48(BN)(6) using density functional calculations. The lowest energy structure is one in which B-N bonding is present as boron and nitrogen occupy each of the 12 pentagons of the fullerene cage. The cluster is polar with a net dipole moment of 0.55 D, which indicates an enhanced tendency toward reactivity with other media. The excitation spectrum shows that the lowest transition of 1.75 eV is dipole-allowed. The optical gap Of C-48(BN)(6) is redshifted by 1.17 eV relative to that Of C-60, suggesting possible use as single-molecule fluorescent probes for various applications. (C) 2004 Elsevier B.V. All rights reserved.