标题：Multi-Copper-Mediated DNA Base Pairs Acting as Suitable Building Blocks for the DNA-Based Nanowires
作者：Genqin Li;Haiying Liu;Xiaohua Chen
作者机构：[Li, G] Center of Modeling and Simulation Chemistry, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, China;[ Liu, H] Center of 更多
通讯作者地址：[Bu, YX]Shandong Univ, Inst Theoret Chem, Ctr Modeling & Simulat Chem, Jinan 250100, Peoples R China.
来源：The journal of physical chemistry, C. Nanomaterials and interfaces
摘要：Transition-metal-mediated base pairs are under intense research because of their potential application in nanoscale molecular devices. To pursue suitable building blocks for DNA-based molecular wires, a three-copper-mediated guanine- cytosine (G_(3Cu)C) and a two-copper-mediated adenine-thymine (A_(2Cu)T) base pair were designed by equi-stoichiometric H-by-Cu replacements in this Article. Their structural and electronic properties were examined by theoretical methods. Geometrically, G_(3Cu)C and A_(2Cu)T have great resemblances to the natural GC and AT with a size-expansion of about 1.0 A due to the larger radii of Cu(l). Their significantly larger binding energies promise them to be structurally suitable for DNA helix construction. Electronically, the equi-number H-by-Cu replacement not only leads to considerable reductions of the HOMO-LUMO gaps and ionization potentials, but also enhances transverse electronic communication within isolated G_(3Cu)C and A_(2Cu)T pairs, revealed by the charge-transfer transitions in the UV absorption spectra of G_(3Cu)C and A_(2Cu)T. To further examine the effect of H-by-Cu substitution on conductivity, three-layer-stacked G_(3Cu)C and A_(2Cu)T of repeat and cross sequences were studied with positive results obtained. It can be reasonably concluded that the multi-Cu-mediated G_(3Cu)C and A_(2Cu)T pairs are promising candidates for building blocks of the Cu_m-DNA nanowires. This work would open a new prospective for rational design of the DNA-based molecular wires by multimetal incorporation.