Absorption and Emission Spectra of a Flexible Dye in Solution: a Computational Time-Dependent Approach.
Absorption and Emission Spectra of a Flexible Dye in Solution: a Computational Time-Dependent Approach.
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DOI：
10.1021/ct4005799
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发表时间：
2013-10-08
影响因子：
5.5
通讯作者：
Barone V
中科院分区：
文献类型：
--
作者：
De Mitri N;Monti S;Prampolini G;Barone V
在含时密度泛函理论框架下，采用经典动态采样和量子力学描述相结合的综合计算策略，研究了有机发色团4-naphthoyloxy-1-methoxy-2，2，6，6-tetramethylpiperidine(NFO-TEMPO-Me)在甲苯溶液中的光谱性质。原子模拟基于精确的参数化力场，专门设计来表示分子在基态和亮激发态的构象行为，而TDDFT计算是通过选择混合泛函和基组的组合来执行的，以获得与实验结果非常匹配的光谱。溶剂效应对获得良好的准确性至关重要，通过显式的分子和可极化的连续统描述来考虑。尽管在甲苯的情况下，特定的溶剂化作用不是基本的，但溶液中详细的构象采样已经证实了动态描述分子几何对于可靠地描述染料的光物理性质的重要性。建立了理论数据和实验数据之间的一致性，并建立了用于预测柔性荧光团在溶液中的光学行为的稳健的协议。
The spectroscopic properties of the organic chromophore 4-naphthoyloxy-1-methoxy-2,2,6,6-tetramethylpiperidine (NfO-TEMPO-Me) in toluene solution are explored through an integrated computational strategy combining a classical dynamic sampling with a quantum mechanical description within the framework of the time-dependent density functional theory (TDDFT) approach. The atomistic simulations are based on an accurately parametrized force field, specifically designed to represent the conformational behavior of the molecule in its ground and bright excited states, whereas TDDFT calculations are performed through a selected combination of hybrid functionals and basis sets to obtain optical spectra closely matching the experimental findings. Solvent effects, crucial to obtain good accuracy, are taken into account through explicit molecules and polarizable continuum descriptions. Although, in the case of toluene, specific solvation is not fundamental, the detailed conformational sampling in solution has confirmed the importance of a dynamic description of the molecular geometry for a reliable description of the photophysical properties of the dye. The agreement between theoretical and experimental data is established and a robust protocol for the prediction of the optical behaviour of flexible fluorophores in solution is set.