Ma Fang, Bai Dongsheng, Xu Hongliang
School of Chemistry and Materials Science, Huaibei Normal University, Huaibei, 235000, China,
J Mol Model. 2014 Dec;20(12):2532. doi: 10.1007/s00894-014-2532-x. Epub 2014 Nov 30.
We present a theoretical investigation of the electric properties of two kinds of one-dimensional lithium bonded chains: (NC-Li)n and (NC-CC-Li)n (n = 1-8). The resulting (NC-Li)n and (NC-CC-Li)n were found to exhibit enhanced first hyperpolarizabilities (β 0) with increasing n, and a slight change in the absorption maximum wavelength λmax at the crucial transition. Comparing with (NC-Li)n, (NC-CC-Li)n exhibited particularly drastically enhanced β 0 values due to clearly enhanced coupled oscillators and double-degenerated charge transitions. β 0 is known to be the microscopic origin of the second-order non-linear optical (NLO) property, and λmax is an approximate measure of the transparency achievable, thus both are important indices of high-performance NLO molecules. Therefore, our investigations into one-dimensional lithium bond chains will be beneficial to understanding the relationship between β 0 and λmax, thus aiding the design of one-dimensional NLO materials with excellent transparence-efficiency.
(NC-Li)n 和 (NC-CC-Li)n（n = 1 - 8）的电学性质进行了理论研究。结果发现，随着 n 的增加，(NC-Li)n 和 (NC-CC-Li)n 的第一超极化率（β0）增强，并且在关键跃迁处吸收最大波长 λmax 有轻微变化。与(NC-Li)n 相比，(NC-CC-Li)n 由于耦合振荡器明显增强和电荷跃迁双重简并，其 β0 值显著增强。已知 β0 是二阶非线性光学（NLO）性质的微观起源，而 λmax 是可实现透明度的近似度量，因此两者都是高性能 NLO 分子的重要指标。所以，我们对一维锂键链的研究将有助于理解 β0 和 λmax 之间的关系，从而有助于设计具有优异透明效率的一维 NLO 材料。
