Amino acids, mean excitation energy

Comparison of these calculated numbers with the little experimental and other theoretical data available (see Table 5.4) indicates that the numbers produced here should produce amino acid mean excitation energies reliable at the level of a few percent. 

J.R. Sabin, J. Oddershede, S.P.A. Sauer, Amino Acid Mean Excitation Energies and Directional Dependencies from Core and Bond Calculations, AlP Conf. Proc. CP1080 (2008) 138. 

The Mean Excitation Energy of the Amino Acids and Polypeptides 229... 

THE MEAN EXCITATION ENERGY OF THE AMINO ACIDS AND POLYPEPTIDES... 

The mean excitation energies (/o) for several amino acids, along with the few other values available from experiment (E) and theory (T), and are given in Table 5.4. 

Table 5.4 Calculated Mean excitation energies of some amino acids...

The anisotropy of fhe purine nucleobases is larger than that of fhe pyrimidines, which is attributable to the larger physical extension in the direction of the molecular plane. The mean excitation energy of fhe nucleobases is also more anisotropic than in the case of fhe amino acids, which is caused by the fact that the nucleobases include planar heterocycles with conjugated 7T-bonds. 

The summary of these studies [5-10] reviewed here is that the amino acids and the nucleic acids all have similar properties with regard to absorption of energy from swift ions. All of fhe biomolecules reported here, including water, have mean excitation energies in the neighborhood of 70 eV. Thus, neither malevolent nor therapeutic radiation would be expected to preferentially interact with any particular class of biomolecules. 

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