Nucleosides, mean excitation energies

Table 5.7 Mean excitation energies of five nucleosides...

Comparison with Table 5.5 shows that increasing the complexity of the system, in this case, by forming fhe nucleoside from fhe nucleobase has little effect on the mean excitation energy of fhe sysfem. 

Consider a nucleotide made up of a nucleoside and one fo fhree phosphafe groups. If the nucleoside is composed of a nucleobase confaining N elecfrons, and there are M phosphate groups in the nucleotide, then the mean excitation energy of the nucleotide can be written as follows ... 

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