@article {1585, title = {DFT calculation of core-electron binding energies of pyrimidine and purine bases}, journal = {International Journal of Quantum Chemistry}, volume = {106}, number = {13}, year = {2006}, note = {ISI Document Delivery No.: 082IQTimes Cited: 12Cited Reference Count: 12Takahata, Yuji Okamoto, Andre K. Chong, Delano P.13th Brazilian Symposium of Theoretical ChemistryNOV 20-23, 2005Sao Pedro, BRAZILNatl Res Council, CAPES, Rede Nanotecnol Mole \& Interfaces, FAPESP, FAPERJ, FAPDFSp. Iss. SI}, month = {Nov}, pages = {2581-2586}, type = {Proceedings Paper}, abstract = {We calculated the accurate core-electron binding energies (CEBEs) of pyrimidine and purine bases in their isolated forms in the gas phase, i.e., uracil (U), thymine (T), cytosine (C), adenine (A), and guanine (G), using density functional theory (DFT) with the scheme Delta E (PW86-PW91)/TZP//HF/6-31G*. The relative magnitude of calculated CEBEs of the same type of atom in the gas phase pyrimidine and purine bases reflect its chemical environment. Comparison between the calculated CEBEs of the bases in the gas phase and observed CEBEs of the same molecules in the solid state permitted estimation of the approximate work functions (WD). Using the approximate WD, it was possible to calculate approximate CEBEs of the DNA bases in the solid state. The average absolute deviation from experiment was 0.37 eV. (C) 2006 Wiley Periodicals, Inc.}, keywords = {ACCURATE, CEBE, DFT, DNA bases, ESCA, SHIFTS}, isbn = {0020-7608}, url = {://000240380400006}, author = {Takahata, Y. and Okamoto, A. K. and Chong, D. P.} }