Structures of Solvent-Free, Monomeric LiCCH, NaCCH, and KCCH
Douglas B Grotjahn1, Aldo J Apponi2, Matthew A Brewster2
1Department of Chemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1030 (USA), Fax: (+1) 619-594-4634.
Angewandte Chemie (International Ed. in English)
|May 2, 2018
Summary
Researchers synthesized the simplest alkali metal acetylides (MCCH) in the gas phase for the first time. Millimeter/submillimeter spectroscopy revealed the shortest known M-C bond lengths in organoalkali metal compounds.
Area of Science:
- Inorganic chemistry
- Physical chemistry
- Spectroscopy
Background:
- Alkali metal acetylides (MCCH) are simple compounds with potential applications.
- Previous studies have not synthesized these compounds in the gas phase or precisely determined their bond lengths.
Purpose of the Study:
- To synthesize the simplest alkali metal acetylides (MCCH) in the gas phase.
- To determine the M-C bond lengths of these compounds using high-resolution spectroscopy.
- To provide accurate experimental data for testing theoretical models of chemical bonding.
Main Methods:
- Gas-phase synthesis of MCCH compounds.
- Millimeter/submillimeter spectroscopy of isotopomers.
- High-precision determination of M-C bond lengths (rCM).
Main Results:
- Successful synthesis of MCCH in the gas phase for the first time.
- Determination of the shortest known M-C bond lengths in organoalkali metal compounds.
- Precise measurement of the Li-C bond distance in LiCCH (1.888 ± 0.0005 Å).
Conclusions:
- The synthesis and characterization of MCCH provide fundamental insights into alkali metal bonding.
- The precise experimental bond lengths offer a benchmark for theoretical calculations.
- This work opens new avenues for studying alkali metal organometallic compounds.
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