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Gas-to-solid shift of C 1s-excited benzene
R Flesch1, E Serdaroglu, F Blobner
1Physikalische und Theoretische Chemie, Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
Physical Chemistry Chemical Physics : PCCP
|February 8, 2012
Summary
This study precisely measures the gas-to-solid shift in benzene
Area of Science:
- Physical Chemistry
- Surface Science
- Spectroscopy
Background:
- Understanding molecular phase transitions is crucial in physical chemistry.
- Core-level spectroscopy provides insights into electronic structure changes upon condensation.
- Previous studies have reported varying gas-to-solid shifts for benzene.
Purpose of the Study:
- To accurately determine the gas-to-solid spectral shift for benzene's C 1s → π* transition.
- To compare the gas-to-solid shift with gas-to-cluster shifts and previous experimental data.
- To investigate the influence of structural properties on core-level spectral shifts.
Main Methods:
- Simultaneous gas-phase and condensed-phase C 1s-core level spectroscopy of benzene.
- High-resolution investigation of the C 1s → π* transition (284.0–286.5 eV).
- Ab initio calculations to support the interpretation of spectral shifts.
Main Results:
- A red-shift of 55 ± 5 meV was observed for the C 1s → π* transition in solid benzene compared to the gas phase.
- The gas-to-solid shift is smaller than previously reported values and also smaller than the gas-to-cluster shift.
- Changes in the C 1s → π* band shape upon solidification and cluster formation were analyzed.
Conclusions:
- The measured gas-to-solid shift provides a precise value for benzene condensation.
- The findings challenge previous experimental data and theoretical estimates.
- Structural properties of condensed benzene and molecular clusters influence core-level spectral shifts.
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