NEW METAL DICARBIDES IN THE LABORATORY AND IN SPACE

Changala, Bryan

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https://hdl.handle.net/2142/122339 Copy

Description

Title

NEW METAL DICARBIDES IN THE LABORATORY AND IN SPACE

Author(s)

Changala, Bryan

Contributor(s)

• McCarthy, Michael C
• Gupta, Harshal

Issue Date

2023-06-22

Keyword(s)

Astronomy

Abstract

We present a joint laboratory, theoretical, and astronomical study of several new metal-carbon clusters including the alkaline earth metal-bearing molecules MgC₂, CaC₂, and SrC₂, as well as the closely related rare earth molecule YbC₂. We have synthesized these species in the laboratory with a laser-ablation supersonic expansion source and detected their rotational spectra at high resolution with cavity Fourier transform microwave spectroscopy. Combining extensive isotopic measurements with highly accurate ab initio rovibrational calculations, we have derived their precise semi-experimental equilibrium geometries, which are all T-shaped with highly ionic metal-carbon bonds. Our measured laboratory rest frequencies have enabled the identification of MgC₂ and CaC₂ as the carriers of several strong, previously unassigned radio emission lines in the circumstellar envelope of the well known evolved carbon-rich star IRC+10216. These laboratory and astronomical discoveries yield fundamental insights into the chemical structure and bonding of s- and f-block metal compounds, and place critical new constraints on the postulated astrochemical pathways that incorporate metal atoms into complex polyatomic molecules. Our work suggests that larger metal-carbon clusters may now be detectable in the laboratory and in circumstellar environments, providing a new probe of the formation of refractory metal-carbon particles.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Handle URL

https://hdl.handle.net/2142/122339

DOI

https://doi.org/10.15278/isms.2023.6878

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