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SF₆⁺: Stabilizing Transient Ions in Helium Nanodroplets.

ABSTRACT: There are myriad ions that are deemed too short-lived to be experimentally accessible. One of them is SF₆⁺. It has never been observed, although not for lack of trying. We demonstrate that long-lived SF₆⁺ can be formed by doping charged helium nanodroplets (HNDs) with sulfur hexafluoride; excess helium is then gently stripped from the doped HNDs by collisions with helium gas. The ion is identified by high-resolution mass spectrometry (resolution m/Δm = 15000), the close agreement between the expected and observed yield of ions that contain minor sulfur isotopes, and collision-induced dissociation in which mass-selected He_nSF₆⁺ ions collide with helium gas. Under optimized conditions, the yield of SF₆⁺ exceeds that of SF₅⁺. The procedure is versatile and suitable for stabilizing many other transient molecular ions.

SUBMITTER: Albertini S

PROVIDER: S-EPMC8154854 | biostudies-literature |

REPOSITORIES: biostudies-literature

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