Orientation Construction And Electronic Structure Of M/I(M=Ag, Cu, Pb) Coordination Polymers Directed By Cations

Construction of organic/inorganic hybrid coordination polymers with structural direction agents(SDA) from weak interactions has become the hot research field due to their potential applications in biological conduct material, opt-electronic material and computation chip. So far, study aboutâ… B andâ…£B metal iodides using SDAs is just on ascending.And furthermore, the effects of SDA on their geometric configurations, eletronic structures and properties are still unclear. So it is significant to combine the design synthesis and structural characterization to investigate their electronic properties, tuning rules of structure and properties with quantum chemistry methods. Based on the principle of supramolecular self-assembly, we selected several SDAs with flexible or rigid structures to carry out orientation construction ofâ… B andâ…£B metal iodides. Furthermore, their spectrum, thermal properties and optical limiting effect are measured. And ultimately, CASTEP and G03 programs based on DFT frame were used to calculate their band structures, bonding characters and electronic essence of optical property. So far we have made achievements on the following aspects:1. Twenty fiveâ… B andâ…£B metal iodides were synthesized and sturcuturally characterized with X-ray single crystal diffractometer method. They present versatile structural arrangement from 1-D chain to 3-D network corresponding to different property SDAs. Especially, compound 14 is the first example of exhibiting mixed types of chains in one crystal lattice directed by one cations. And Ag/I three-dimensional network polyer in 17 hasn't been reported so far.2. Quantum chemistry studies based on GGA/PW91 calculation with CASTEP program was carried out to investigate the bonding nature and the electronic structure of target compounds. A significant feature of the result is their transformation of conductor-semiconductor-insulator as tuned by different SDAs. Eg(band gap) of compound 2~5 decrease with increase of chain length(n) of SDAS, their Eg are controlled by valence band of Ag-4d/I-5p. Comparably, Eg of compound 6~9 increase with lengthening of chain length(n) of SDAS, their Eg are determined by conduction band of N-2p. These changing rules of Eg provide...