Structural symmetry breaking in octupolar tetrastyrylpyrazines and their dipole moments in equilibrium ground and Franck-Condon excited state
作者:N.A. Nemkovich、H. Detert、V. Schmitt
DOI:10.1016/j.jphotochem.2017.07.012
日期:2018.3
From electrooptical absorption measurements (EOAM) follows that the dipole moment of octupolar tetrastyrylpyrazines in the equilibrium ground state is large and that the change of dipole moments upon transition to the excited Franck–Condon state is significant. Obtained results unambiguously testify to structural symmetry breaking in the studied octupolar tetrastyrylpyrazines. Molecular mechanics and
根据电光吸收测量(EOAM),八极四苯乙烯基吡嗪在平衡基态下的偶极矩很大,跃迁到激发的Franck-Condon态时偶极矩的变化很明显。获得的结果清楚地证明了所研究的八极四苯乙烯基吡嗪类化合物的结构对称性破裂。分子力学和半经验计算证明四苯乙烯基吡嗪具有非平面构型。分子的非平面的几何形状会导致大的μ克值和偶极矩Δ的显著变化一个μ激励之后。 由于大的μ克和Δ一个μ值在各种溶剂中的研究tetrastyrylpyrazines的第一吸收带和荧光带的最大值转移到长波长区域具有增加溶剂极性。在溶剂的红移过程中,染料的吸收光谱和荧光光谱都不会改变形状。这种现象证明了染料与环境的范德华通用相互作用的决定性作用,即分散性,取向性和诱导性。