کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5416284 | 1506884 | 2010 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
A theoretical study on the substituent effect of DNA-photocleavage by [Ru(phen)2(6-R-dppz)]2+ (RÂ =Â H, OH, and NO2)
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A theoretical study was conducted on the effects of three substituents in the Ru(II) polypyridyl complex, [Ru(phen)2(6-R-dppz)]2+, (RÂ =Â H for complex 1, OH for complex 2, and NO2 for complex 3), on the photocleavage of DNA. The geometric and electronic structures of these complexes in the ground (S0), first singlet (S1), and triplet (T1) excited states, were calculated using the density functional theory (DFT), Hartree-Fock (HF), and configuration interaction singles (CIS) methods. The excited reduction potentials of the Ru(II) complexes in aqueous solution, which appear to be primarily responsible for the DNA-photocleavage behavior, were calculated by thermodynamic cycle, and determined to be higher than the oxidation potentials of some DNA-bases. The order of the reduction potentials changes from 3Â >Â 2Â >Â 1 in the ground state to 2Â >Â 1Â >Â 3 in the excited state, suggesting that the substituent on the main ligand has a significant effect on the electrochemical properties of the excited Ru(II) polypyridyl complexes. In addition, these theoretical results can explain two experimentally-observed phenomena: (a) the cleavage of DNA by complex 3 in the absence of light irradiation; (b) the inability of complex 3 to emit luminescence in its excited triplet state in aqueous solution.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 961, Issues 1â3, 15 December 2010, Pages 35-41
Journal: Journal of Molecular Structure: THEOCHEM - Volume 961, Issues 1â3, 15 December 2010, Pages 35-41
نویسندگان
Lian-cai Xu, Qian-shu Li, Zhi-qiang Zhang, Ti-fang Miao, Kang-cheng Zheng, Liang-nian Ji,