Premium
Rotationally Resolved Electronic Spectroscopy of 1,4‐Benzodioxan: The Anomeric Effect in the Ground and Electronically Excited State
Author(s) -
Chau Vu Thi Bao,
Brand Christian,
Meerts W. Leo,
Schmitt Michael
Publication year - 2011
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201000576
Subject(s) - excited state , chemistry , ground state , atomic physics , molecular orbital , electronic structure , spectroscopy , singlet state , molecular physics , molecule , computational chemistry , physics , organic chemistry , quantum mechanics
We measured the rotationally resolved electronic spectra of the origin and of three vibronic bands of 1,4‐benzodioxan. From comparison to various ab‐initio‐calculated structures of 1,4‐benzodioxan, the twisted C 2 symmetric 1,4‐benzodioxan was shown to be responsible for all the observed spectral features. We analyzed the inertial defects in both electronic states as sensitive indicators of the non‐planarity of the system. The molecule was found to be more planar in the electronic ground state than in the electronically excited singlet state. This effect can be traced back to an increased puckering of the dioxan ring, which also comprises the oxygen atoms, in the excited state. This observation is discussed in terms of natural bond orbitals.