Schneider Michael, Wilke Martin, Hebestreit Marie-Luise, Henrichs Christian, Meerts W Leo, Schmitt Michael
Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Chemie I, 40225, Düsseldorf, Germany.
Radboud University, Institute for Molecules and Materials, Felix Laboratory, Toernooiveld 7c, 6525 ED, Nijmegen, The Netherlands.
Chemphyschem. 2018 Feb 5;19(3):307-318. doi: 10.1002/cphc.201701095. Epub 2018 Jan 9.
Rotationally resolved electronic Stark spectra of rotamers of 1,2-, 1,3-, and 1,4-dimethoxybenzene have been recorded and analyzed using evolutionary strategies. The experimentally determined dipole moments as well as the transition dipole moments are compared to the results of ab initio calculations. For the electronic ground states of the experimentally observed dimethoxybenzenes, the permanent dipole moments can be obtained from vectorial addition of the monomethoxybenzene dipole moment. However, this is not the case for the electronically excited states. This behavior can be traced back to a state mixing of the lowest electronically excited singlet states for the asymmetric rotamers. For the symmetric rotamers however, this is not valid. We discuss several possible reasons for the non-additivity of the dipole moments in the excited states of the symmetric rotamers.
已使用进化策略记录并分析了1,2 -、1,3 -和1,4 -二甲氧基苯旋转异构体的旋转分辨电子斯塔克光谱。将实验测定的偶极矩以及跃迁偶极矩与从头算计算结果进行了比较。对于实验观察到的二甲氧基苯的电子基态，永久偶极矩可通过单甲氧基苯偶极矩的矢量相加得到。然而，对于电子激发态并非如此。这种行为可追溯到不对称旋转异构体最低电子激发单重态的态混合。然而，对于对称旋转异构体，情况并非如此。我们讨论了对称旋转异构体激发态中偶极矩非加和性的几个可能原因。
