We study the electronic structure of CdTe spheres (dots) and tetrapods by absorption, fluorescence, and photoluminescence-excitation (PLE) spectroscopy. A series of quantum dots with different diameter and tetrapods with varying arm length and diameter is investigated in solution at room temperature. We observe a significant impact of the geometrical shape of the nanocrystals on the optical response. In particular we find a double peak in the emission of tetrapods as a characteristic feature of this nanocrystal geometry. We observe a pronounced Stokes shift for the tetrapod and dot samples which depends sensitively on the crystal size. (c) 2005 Elsevier Ltd. All rights reserved.