以芘为中心系列衍生物的单光子和双光子吸收特性理论研究

在含时密度泛函理论的水平上，利用响应场理论方法研究了以芘为中心系列衍生物的单光子和双光子吸收特性. 研究结果表明，在低能量范围内，每个分子有多个电荷转移态. 单光子吸收性质与实验结果符合较好. 随着分子尺寸的增加，分子的最大双光子吸收截面显著增加，其中具有四分枝结构分子的最大双光子吸收截面是单枝结构分子的5.6倍. 同时，分子的双光子吸收截面与分子结构的对称性有关.其中对称结构分子具有较大的双光子吸收截面.

Theoretical Studies on One-photon and Two-photon Absorption Properties of Pyrene-core Derivatives

The analytic response theory at density functional theory level is applied to investigate one-photon and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical results show that there are a few charge-transfer states for each compound in the lower energy region. The one-photon absorption properties of the five investigated compounds are highly consistent with those given by experimental measure-ments. The two-photon absorption intensities of the compounds are greatly enhanced with the increments of the molecular sizes, in which the two-photon absorption cross section of the four-branched compound is about 5.6 times of that of the mono-branched molecule. Further-more, it is shown that the two-photon absorption properties are sensitive to the geometrical arrangements.