DNA分子链电子结构特性研究

在单电子紧束缚近似下，建立了一维无序二元DNA分子链模型，计算了链长为2×10⁴个碱基对的DNA分子链的电子态密度、局域化特性，并探讨了碱基对的不同组分、格点能量无序度对电子局域态的影响.结果表明：由于DNA分子链中格点能量无序及碱基对的不同组分的存在，其电子波函数呈现出局域化的特性，而局域长度作为衡量电子局域化程度的一个尺度，受碱基对的组分及格点能量无序度的影响.关键词：DNA分子链电子结构电子局域态局域长度

Characteristics of the electronic structure of DNA sequence

Based on a tight-binding disordered model describing a single electron band, we establish a one-dimensional disordered binary DNA model, and calculate the density of electronic states，the localization property of electronic wave-function and the localization length of a DNA sequence with 2×10⁴ nucleotide base pairs. We also investigate the effect of composition of nucleotide base pairs, the degree of disorder of the energy base pairs on the localization length. The results indicate that the electronic states of DNA sequence are localized due to the compositional disorder of nucleotide base pairs and the energy disorder of the lattices, and the localization length is dependent on the composition of nucleotide base pairs and the disorder degree of lattices energy.