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N Sane

Publications and source records attributed to N Sane.

3 recordsLinked to original sources

Classification of organic molecules to obtain electron affinities from half-wave reduction potentials: cytosine, uracil, thymine, guanine and adenine.

A procedure for obtaining the adiabatic electron affinities (AEA) of organic molecules from half-wave reduction potentials in aprotic solvents is presented. Molecules are placed into groups according to their structure. Each group has a different solution energy difference. Calculations of AEA and charge distributions with AM1-multiconfiguration configuration interaction are used to support the intuitive classification of the molecules. The procedure is illustrated for Vitamins A and E, riboflavin, the azines, polyenes, hydroxy-pyrimidine, oxo-guanine, the hydrogen bonded cytosine-oxo-guanine as well as the AEA, and vertical EA (VEA) of Cytosine (C), Uracil (U), Thymine (T), Guanine (G) and Adenine (A). The latter values are: (VEA) G, 0.10; A, -0.49; U, 0.33; T, 0.31; C, -1.48 and (AEA) G, 1.51 +/- 0.05; A, 0.95 +/- 0.05; U, 0.80 +/- 0.05; T, 0.79 +/- 0.05; C, 0.56 +/- 0.05 in eV.

Adenine↗

The electron affinities of the radicals formed by the loss of an aromatic hydrogen atom from adenine, guanine, cytosine, uracil, and thymine.

The major ion formed in Negative Ion Chemical Ionization Mass Spectrometry of Adenine, Guanine, Cytosine, Uracil and Thymine is the dehydrogenated anion. The CURES EC procedure for optimizing Austin Model-1 Multiconfigurational Configuration Interaction semi-empirical calculations is applied to the electron affinities of the corresponding dehydrogenated bases and N-H bond dissociation energies. These calculated values will be compared with literature values of the gas phase acidities of the purines and pyrimidines. The N-H bond dissociation energies are about 3.95 eV for Guanine, Adenine, and Thymine and 4.08 eV for Cytosine and Uracil. The electron affinities of the radicals are AMinH = 3.50 eV, GMinH = 3.46 eV, CMinH = 3.38 eV, UMinH = 3.48 eV, TMinH = 3.46 eV.

Adenine↗