标题:Radical-Radical Interactions among Oxidized Guanine Bases Including Guanine Radical Cation and Dehydrogenated Guanine Radicals
作者:Jing Zhao;Mei Wang;Hongfang Yang
作者机构:[Zhao, J] School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China;[ Wang, M] School of Chemistry and Chemical Engineer 更多
通讯作者:Bu, Y
通讯作者地址:[Bu, YX]Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.
来源:The journal of physical chemistry, B. Condensed matter, materials, surfaces, interfaces & biophysical
出版年:2013
卷:117
期:37
页码:10698-10710
DOI:10.1021/jp4042149
摘要:We present here a theoretical investigation of the structural and electronic properties of di-ionized GG base pairs (G~(·+)G~(·+),G(-H1)~·G~(·+), and G(-H1)~·G(-H1)~·) consisting of the guanine cation radical (G~(·+)) and/or dehydrogenated guanine radical (G(-H1)~·) using density functional theory calculations. Different coupling modes (Watson-Crick/WC, Hoogsteen/Hoog, and minor groove/min hydrogen bonding, and π-π stacking modes) are considered. We infer that a series of G~(·+)G~(·+) complexes can be formed by the high-energy radiation. On the basis of density functional theory and complete active space self-consistent (CASSCF) calculations, we reveal that in the H-bonded and N-N cross-linked modes, (G~(·+)G~(·+))_(WC), (G(-H1)~·G(-H1)~·)_(WC), (G(-H1)~·G(-H1)~·)_(minI), and (G(-H1)~·G(-H1)~·)_(minIII) have the triplet ground states; (G~(·+)G~(·+))_(HoogI), (G(-H1)~·G~(·+))_(WC), (G(-H1)~·G~(·+))_(HoogI), (G(-H1)~·G~(·+))_(minI), (G(-H1)~·G~(·+))_(minII), and (G(-H1)~·G(-H1)~·)_(minII) possess open-shell broken-symmetry diradical-characterized singlet ground states; and (G~(·+)G~(·+))_(HoHo), (G~(·+)G~(·+))_(minI), (G~(·+)G~(·+))_(minII), (G~(·+)G~(·+))_(minIII), (GG~(·+))_(HoHo)) (G(-H1)~·G~(·+))_(minIII)(G(-H1)~·G~(·+))_(HoHo)), and (G(-H1)~·G(-H1)~·)_(HoHo) are the closed-shell systems. For these Hbonded diradical complexes, the magnetic interactions are weak, especially in the diradical G~(·+)G~(·+) series and G(-H1)~·G(-H1)~· series. The magnetic coupling interactions of the diradical systems are controlled by intermolecular interactions (H-bond, electrostatic repulsion, and radical coupling). The radical-radical interaction in the π-π stacked di-ionized GG base pairs ((G~(·+)G~(·+))_(ππ) (G\'(-H1)~·G~(·+))_(ππ), and (G(-H1)~·G(-H1)~·)_(ππ) are also considered, and the magnetic coupling interactions in these π-π stacked base pairs are large. This is the first theoretical prediction that some di-ionized GG base pairs possess diradical characters with variable de
收录类别:EI;SCOPUS;SCIE
WOS核心被引频次:1
Scopus被引频次:1
资源类型:期刊论文
原文链接:https://www.scopus.com/inward/record.uri?eid=2-s2.0-84884506314&doi=10.1021%2fjp4042149&partnerID=40&md5=7918cb46a73c380ce7b714693a90c3c9
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