Infrared Signatures of Proton Transfer in Guanine⋅Cytosine and Adenine⋅Thymine Base Pairs: DFT Study
نویسندگان
چکیده
The structures of all stable tautomers of guanine⋅cytosine and adenine⋅thymine Watson–Crick base pairs produced by single and double proton transfers from the most stable structures are optimized using density functional theory (DFT) at the B3LYP/6-31G(d,p) level. The zwitterionic tautomer of guanine⋅cyosine is stable in a high-dielectric medium (water), but not in the gas phase. Normal mode calculations show that the infrared peak positions and intensities of the carbonyl, N–H, and O–H stretching modes are sensitive to the tautomer
منابع مشابه
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