Abstract
We report a temperature-controlled photoelectron imaging study of SbO2–, produced from a laser vaporisation source and cooled in a cryogenic 3D Paul trap. Vibrationally resolved photoelectron spectra are obtained for the ground state detachment transition, yielding the bending frequencies for both SbO2 and SbO2–. Franck-Condon simulations also allow the estimate of the vibrational temperature of the trapped SbO2– anion. A near-threshold spectrum of SbO2– at a photon energy of 3.4958 eV reveals partially resolved rotational structure for the 0–0 transition, which yields an accurate electron affinity of 3.4945 ± 0.0004 eV for SbO2. The rotational simulation also yields an estimated rotational temperature of the trapped ions.
Acknowledgements
This paper is dedicated to the memory of Prof. Dieter Gerlich. One of us (PI: L.S.W.) would like to thank Prof. Dieter Gerlich for his support and discussion when he was developing the first cryogenically-cooled 3D Paul trap [Citation6,Citation7]. When the PI was preparing the design of this instrument, he invited Dieter to Richland, Washington for consultation. Much to his surprise, Dieter told him that the 3D Paul trap would not work and instantly offered the PI his 22-pole ion trap design! After the PI realised that the dimension of Dieter’s 22-pole ion trap was similar to the commercially available Paul trap, he went ahead with his original plan, reasoning that if it did not work he could easily switch to the 22-pole trap design. Dieter even connected the PI to have a decommissioned 22-pole ion trap from Taiwan shipped to the PI then at Richland, Washington, which was eventually shipped back to Dieter in Germany after the 3D Paul trap design was shown to be effective in cooling trapped ions from an electrospray ion source [Citation6–11].
Disclosure statement
No potential conflict of interest was reported by the author(s).