We investigated the electronic structure,photophysical properties,and thermal stability of N-(3-trimethoxysilylethyl)ethylenediamine (TMSEEDA).The optimized structural parameters in the ground state and first excited state were obtained from density functional theory calculations.The results showed that there was probably rr electron delocalization within the Si - O skeleton,which induced the long wavelength absorption.A broad and intense blue emission with a maximum at 430 nm was observed for both the solution and the solid state with 270 nm excitation at room temperature.The absorption intensity for the solid state was five-times that of the pure TMSEEDA.For the ethanol solution,the photoluminescence intensity increased with increasing concentration of TMSEEDA and reached a maximum at a concentration of 100％.These results suggest there is no concentration quenching for TMSEEDA.An accepted model of electron delocalization and d-p rr-bonding within the Si- O skeleton was applied to explain the long wavelength absorption and blue emission.%详细研究了N-(3-三甲氧基硅基乙基)乙二胺(TMSEEDA)的电子结构、光物理性质以及热稳定性.通过密度泛函理论计算获得了基态和第一激发态的结构参数.计算结果还表明在Si-O骨架内存在离域电子,这导致了长波长的吸收.在270 nm紫外光的激发下,溶液和固态均能观察到一个宽且强的蓝色发射,其峰位于430nm,固态的强度高出纯物质5倍左右.在乙醇溶液中,发光强度随着TMSEEDA浓度的增大而增加,并在纯物质时达到最大值.这些结果说明TMSEEDA不存在浓度淬灭效应.我们提出了在Si-O骨架内电子离域和d-pπ键模型来解释长波长吸收和蓝色发射.
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