Author/Authors :
Muccini، نويسنده , , M. P. Schlaich، نويسنده , , H. and Feldmann، نويسنده , , J. and Bنssler، نويسنده , , H. and Gِbel، نويسنده , , E.O. and Zamboni، نويسنده , , R. and Taliani، نويسنده , , C. and Erxmeyer، نويسنده , , J. and Weidinger، نويسنده , , A.، نويسنده ,
Abstract :
The low energy optic excitations in crystalline C60 are investigated by linear and non-linear spectroscopic techniques. Two-photon excitation directly locates the lowest purely electronic 0-0 transition at 14 850 cm−1. By the analysis of the Herzberg-Teller induced photoluminescence the lowest forbidden Frenkel exciton is assigned to a T1g excited state. At low temperature, the absorption spectrum exhibits doublet features with constant energetic splitting. The two distinct alignments of neighbouring C60 molecules (merohedral order) might be responsible for the double resonances.
