Simultaneous deposition of mass selected anions and cations: improvements in ion delivery for matrix isolation experiments

Abstract

A focus of the research in our group has been to develop improved methods for ion delivery in matrix isolation experiments. We have previously reported a method to co-deposit low energy, mass selected metal anions and a rare gas counter cation.$^{a}$ A modification allowing for mass selection of both the anion and cation will be discussed. Results from preliminary experiments of mass selected, low energy Cu$^{-}$ and SF$_{5}$$^{+}$ will also be highlighted. To our knowledge, these experiments are the first time two mass selected beams of ions have been simultaneously deposited into a cryogenic matrix. Co-deposition of the ions into an argon matrix doped with 0.02\% CO at 20K resulted in the observation of bands assigned to SF$_{5}$$^{+}$ and anionic copper carbonyl complexes, Cu(CO)$_{n}$$^{-}$ (n=1-3). Upon irradiation of the matrix with a narrow band, blue LED, the copper carbonyl complexes are converted to the neutral analogues, while the fate of the photodetached electrons can be directly tracked, as a decrease of the SF$_{5}$$^{+}$ band and a growth of the neutral SF$_{5}$ band are observed.

$^{a}$Ludwig, R. M.

Moore, D. T.

J. Chem. Phys. 139, 244202 (2013).