amino acids                   I0(eV) glycine 71.1 alanine   67.4   nucleobases   cytosine 69.6 uracil 73.1 thymine 70.0 adenine 69.1 guanine 71.6   nucleoside   cytidine 69.96 uridine 71.41 methyl uridine 70.12 adenosine 69.68 guanosine 70.89

Table 1: Mean Excitation Energies of Some Biomolecules.