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Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Gas phase electronic spectrum of linear AlCCH
Cristina Apetrei1, Hongbin Ding, John P Maier
1Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
Physical Chemistry Chemical Physics : PCCP
|July 20, 2007
Summary
The electronic spectrum of aluminum carbon hydride (AlCCH) was detected using laser ablation and mass spectrometry. This study assigns the observed spectrum to a specific electronic transition, revealing details about its molecular structure and vibrational properties.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Computational Chemistry
Background:
- Aluminum-containing species are important in materials science and astrochemistry.
- Understanding the electronic structure of small molecules provides fundamental insights into chemical bonding.
Purpose of the Study:
- To experimentally detect and characterize the gas-phase electronic spectrum of AlCCH.
- To determine the molecular structure and electronic transition of AlCCH using theoretical calculations and experimental data.
Main Methods:
- Gas-phase electronic spectroscopy utilizing resonant two-color two-photon ionization.
- Laser ablation as a source for generating AlCCH species.
- Density functional theory (DFT) for optimizing molecular structures and calculating excitation energies.
Main Results:
- The electronic spectrum of AlCCH was observed in the 315-355 nm region.
- The spectrum was assigned to the A (1)Pi<-- X (1)Sigma(+) electronic transition of linear AlCCH.
- Vibrational frequencies and molecular constants were determined, indicating a shorter Al-C bond in the excited state.
Conclusions:
- The study provides a detailed characterization of the AlCCH electronic spectrum and its ground and excited states.
- The Renner-Teller effect in the excited state was identified as a significant factor.
- Experimental and theoretical results agree on the molecular geometry and electronic properties of AlCCH.
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