氨酸带的光物理性能 氨酸带的光物理性能
Hyun Sun Cho1, Dae Hong Jeong, Sung Cho
1Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea.
Journal of the American Chemical Society
|December 6, 2002
概括
新的化(II) 氨酸带 (Tn) 显示了快速激发状态形成和加速放松,与直角阵列形成鲜明对比. 这些特性表明在电子和光学中的应用.
科学领域:
- 超分子化学 超分子化学
- 光物理学的光学物理学
- 材料科学 材料科学 材料科学
背景情况:
- 氨酸阵列因其独特的光物理性质而受到研究.
- 化烯结构提供了新的电子和光学特性.
研究的目的:
- 为了研究新型化Zn(II) 氨酸阵列 (氨酸带,Tn) 的光物理性质.
- 为了比较这些合并阵列与直角氨酸阵列的属性.
- 探索氨酸带的潜在应用.
主要方法:
- 稳态和时间分辨率的光谱测量.
- 理论分子轨道 (MO) 的计算 (PPP-SCI).
主要成果:
- 氨酸带的吸收光谱随着颜料数量的增加而转移到红外区域.
- 快速兴奋状态形成 (大约. 500 fs对于T2) 通过内部转化,比单质Zn{\displaystyle \Zn{\text{II}}\porphyrin (1.2 ps) 更快.
- 兴奋状态的放松加速随着氨酸单位的增加 (T2二聚体的4.5psi增加到T6六聚体的0.3psi),由能量差距定律解释.
- 氨酸带的最低激发状态中的Wannier型激子特征,与直接链接的数组中的Frenkel型激子不同.
结论:
- 合烯带表现出独特的光物理特性,与直角阵列不同.
- 观察到的属性归因于化的平面结构和激子的行为.
- 烯酸带显示了电线,红外传感器和非线性光学材料等应用的潜力.
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