The time-dependent DFT (TD-DFT), CIS and TD-HF studies have been performed on the UV-spectrum of phenanthrene. Based on the optimized geometries, the vertical excitation energies were calculated. The effect of basis sets is important on the excitation energies. Different exchange-correlation potentials hardly affected the excitation energies due to that the systematic errors of orbital energies were cancelled each other. The deviations between our theoretical results and experimental ones are in the same order of magnitude as that between different experimental methods. TD-DFT is more satisfactory than CIS and TD-HF on the electronic excitation energy calculations.

Key words: phenanthrene, electronic excitation energy, time-depentent DFT, UV-spectrum