Two-Photon Upconversion Properties Study Of Several Kind New Pyridine Dyes

Two-Photon absorption (TPA) is a quantum process in which an atom or molecule simultaneously absorbs two photons via intermediate virtual state. Due to the high spatial selectivity, excellent media penetrability and unique quantum selection rules of TPA, it can be applied in many aspects, such as: upconversion laser, optical power limiting, three-dimension microfabrication, photodynamics therapy, 3D optical storage, two-photon spectroscopy and two-photon fluorescence imaging etc. The organic strong TPA materials has attracted a great deal of interest because its superior TPA properties. Since 1980s, different research groups had synthesized large numbers of new chromophores with superior TPA properties successively. During the research on the relationships between structure and properties of the chromophores, some experience and design ideas have been realized which are very important in the synthesis of new strong TPA materials. Under the guidance of these experiences, the molecular structure of strong TPA materials had been optimized, and the TPA cross-section had been improved. Due to the broad application prospect of strong TPA materials, we can predict that organic materials with superior TPA properties will become one of hotspots in materials research fields for a longer period.Recently, the research of the strong TPA dyes focused on the styryl skeleton. The molecular structure of this kind dye can be tuned flexibly because of various substituents, therefore, the TPA properties of these dyes were optimized. Up to now, the most reported strong TPA dyes were N-methyl-styryl pyridinium. However, the research of improved dyes was not sufficient. During the processes of exploring new TPA materials, we have successfully synthesized several kinds strong TPA dyes based on the styryl skeleton, i.e. improved pyridinium, organic lanthanide complexes, organic metal complexes. In these materials, some are based on traditional types and some are developed by us. We systematically investigate the relationships of molecular structure and one- and two-photon properties of the above materials, and enriched the research findings. Simultaneously, in terms of the demands of strong two-photon upconversion dye, we got some significative conclusions for the exploring new materials on this aspect.A. The main conclusions and rules of this thesis are as follows: 1. The linear optical properties of dyes...