【摘要】 采用密度泛函理论方法优化了2,4-双(4-二甲胺基-2-二羟苯基)方酸分子的三种氢键结构,计算了分子激发态能量、单光子吸收振子强度和双光子吸收截面,应用洛仑兹展宽模拟了双光子吸收光谱并与实验结果进行了比较,分析了氢键对分子双光子吸收性质的影响.结果表明,氢键可以促进分子内电荷转移,从而显著提高分子双光子吸收强度.更多还原

【Abstract】 Three geometries of 2,4- bis(4- dimethylamino- 2- hydroxyphenyl) squaraine induced by different hydrogen bond structures have been optimized using density functional theory.The excitation energy,the oscillator strength and the two- photon absorption cross section are calculated.The two- photon absorption spectra with Lorentz broadening are simulated for comparison with experiments.The effects of hydrogen bond on two-photon absorption properties of the molecules are analyzed.It is demonstrated that the existence of hydrogen bonds can promote the intra- molecular charge- transfer,thereby enhancing the strength of the two- photon absorption significantly.更多还原