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The microwave spectra of three isotopologues of the gas-phase heterodimer formed between cis-1,2-difluoroethylene and hydrogen chloride are obtained in the 5–21 GHz region using Fourier transform microwave spectroscopy. The molecular structure, determined from the analysis of the spectra and supported by quantum chemistry calculations, has the hydrogen atom of the hydrogen chloride molecule interacting with both fluorine atoms of the fluoroethylene and no interaction between the chlorine atom and the olefin. Although the equilibrium structure has two inequivalent H⋯F interactions, zero-point motion averages over the two equivalent choices for these interactions, rendering the pairs of like atoms (C, H, and F) of the fluoroethylene equivalent, retaining the C2v symmetry of the olefin. This results in only one unique singly substituted 13C isotopologue and in the observed effects on transition intensities due to nuclear spin statistics. The heterodimer structure allows for a strong, linear hydrogen bond between the HCl donor and the fluoroethylene acceptor that is more important here than in the analogous acetylene containing complex, where the interaction between the π electrons of acetylene and an electrophilic hydrogen atom on the olefin compensates for the loss of linearity required for binding to a geminal F/H pair.
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This content will become publicly available on February 5, 2026
Uncovering the substrate of olefin synthase loading domains in cyanobacteria Picosynechococcus sp. strain PCC 7002
We report the heterologous expression of two olefin synthases in PCC 7002 to generate shorter chain α-olefins. Genetic deletions show that membrane-liberated fatty acids are substrates for the chain-length specific loading domain of olefin synthase.
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- Award ID(s):
- 2132036
- PAR ID:
- 10609838
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- RSC Chemical Biology
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2633-0679
- Page Range / eLocation ID:
- 307 to 316
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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