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Updated: Aug 23, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Formation of HArF in solid Ar revisited: are mobile vacancies involved in the matrix-site conversion at 30 K?
Leonid Khriachtchev1, Antti Lignell, Markku Rasanen
1Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014, University of Helsinki, Finland. leonid.khriachtchev@helsinki.fi
Abstract:
The HArF molecule can occupy in solid Ar thermally unstable and stable configurations, and their microscopic structure is not understood at the moment. We present additional experimental results on the formation of two HArF configurations and analyze them with emphasis on possible reactions of the unstable configuration with matrix vacancies to form the stable configuration. We conclude that the existing computational scenarios do not describe fully the present experimental data. In order to explain qualitatively the experimental results, two tentative models are discussed. The first model is based on local mobility of matrix vacancies produced during photolysis and the second model considers isomerization of the HArF at Arn supermolecule. More importantly, the present results constitute the experimental basis for future theoretical studies.
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