吡啶取代的Lindqvist型多酸的线性和非线性光学性质及阳离子检测功能的理论研究

采用密度泛函理论B3LYP方法计算了吡啶取代的Lindqvist型多酸(POMs)的线性(最大吸收波长, λ_max)和非线性光学(NLO)超瑞利散射(HRS)的第一超极化率, β_HRS]性质, 探讨了其作为潜在阳离子检测剂的可能性. 金属离子吸附能计算结果表明, 吡啶取代的Lindqvist型多酸配体与金属离子之间均有较强的相互作用, 相互作用强度大小顺序为Ni²⁺>Cu²⁺>Co²⁺>Fe²⁺>Zn²⁺>Mg²⁺>Ca²⁺. 电子光谱和β_HRS计算结果表明, 引入适当的供、 受电子基团对该多酸配体进行修饰可有效调节线性和二阶NLO性质; 同时, 吡啶取代的Lindqvist型多酸对7种金属离子(Cu²⁺, Zn²⁺, Ca²⁺, Mg²⁺, Ni²⁺, Co²⁺, Fe²⁺)表现出了不同的检测行为.

Theoretical Study on Cation Detection Ability of Pyridine-substituted Lindqvist-type Ployoxometalates Based on Linear and Nonlinear Optical Properties†

Linear(wavelength of maximum absorption, λ_max) and nonlinear optical(hyper-Rayleigh scattering first hyperpolarizability, β_HRS) properties of a series of pyridine-substituted Lindqvist polyoxometalates(POMs) were studied via density functional theory(DFT)-B3LYP method. The potential abilities for metal cation sensor of these Lindqvist POMs were probed. The calculated adsorption energy of metal cation on these Lindqvist POM ligand indicates that the interaction strength of them decreases in the order of Ni²⁺>Cu²⁺>Co²⁺>Fe²⁺>Zn²⁺>Mg²⁺>Ca²⁺. The calculated results indicate that the linear and nonlinear optical properties can be effectively tuned by the introduction of electron donor and acceptor. Meanwhile, pyridine-substituted Lindqvist POM ligands display various detection functional for the seven metal cations(Cu²⁺, Zn²⁺, Ca²⁺, Mg²⁺, Ni²⁺, Co²⁺, Fe²⁺).