Position matters: high resolution spectroscopy of 6-methoxyindole
Christian Brand1, Olivia Oeltermann, Martin Wilke
1Heinrich-Heine-Universität, Institut für Physikalische Chemie I, D-40225 Düsseldorf, Germany.
The Journal of Chemical Physics
|January 17, 2013
Summary
The structures of syn and anti 6-methoxyindole were determined using spectroscopy and ab initio calculations. The study reveals how electronic states and molecular geometry influence transition dipole moments in these molecules.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Computational Chemistry
Background:
- Understanding molecular structure and electronic properties is crucial in chemistry.
- 6-Methoxyindole exists in syn and anti conformers, each with unique structural and electronic characteristics.
Purpose of the Study:
- To determine the ground and excited state structures of syn and anti 6-methoxyindole.
- To investigate the influence of electronic states and molecular geometry on transition dipole moments.
Main Methods:
- Rotationally resolved electronic spectroscopy was employed to analyze molecular structures.
- High-level ab initio calculations, specifically second-order coupled cluster theory, were utilized.
- Rovibronic spectra of seven isotopomers were analyzed.
Main Results:
- The electronic ground and excited state structures of both conformers were elucidated.
- Calculations predicted heavily mixed lowest excited singlet states.
- Transition dipole moments were found to be strongly dependent on molecular geometry.
- The absolute orientation of the transition dipole moment was determined to be L(b)-like for both conformers.
Conclusions:
- The study provides a detailed structural and electronic characterization of 6-methoxyindole conformers.
- The findings highlight the interplay between electronic configuration, molecular geometry, and spectroscopic properties.
- This research contributes to a deeper understanding of excited-state dynamics in substituted indoles.
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