A Quantum Chemical Study of the Structure, Bonding Characteristics and Nonlinear Optical Properties of Aryloxido and Salicylaldehydo Derivatives of [XW5O18](3-) (X = Zr or Ti)

作者：Zhuang Jia; Yan Likai; Liu Chunguang; Su Zhongmin^*

来源：European Journal of Inorganic Chemistry, 2009, 2009(17): 2529-2535.

DOI：10.1002/ejic.200900011

• Polyoxometalates
• Organic-inorganic hybrid composites
• Natural bond analysis
• Nonlinear optics
• Density functional calculations

The bonding characteristics, first hyperpolarizabilities, and origin of the nonlinear optical (NLO) properties of aryloxido and salicylaldehydo derivatives Of [XW5O18](3-) (X = Zr or Ti) have been investigated using density functional theory (DFT). The flexible bonding behavior of the linkage oxygen (O-L) atom attracted our attention initially, and NBO analysis revealed that there aret two different kinds of pi-interactions involving the O-L atom in these systems. In two aryloxido derivatives (systems 1 and 2), O-L-metal pi-interactions are largely O-L-M p-d in character, whereas in the sahcylaldehydo derivatives (system 3) we observed another kind of pi-interaction, namely O-L-C p-p pi-bonding. The differences in molecular composition in our studied systems are very slight. However, the beta(0) values differ significantly. Thus, system 3 has the largest beta(0) value(559.27 x 10(-30) esu), which is 170 times larger than that of system 1. This variation can be traced to the different electronic transitions and charge-transfer characteristics. The heteropolyanion cluster and organic ligand are both electron-rich groups. A small change in molecular composition or architecture can therefore significantly modify the configuration and overlapping of molecular orbitals, thus causing a "butterfly effect" upon the electronic transitions and charge-transfer characteristics tics.

• 出版日期2009-6
• 单位东北师范大学