Acceleration of the chemical reaction of trapped Caions with H₂O molecules by laser excitation

Abstract

The reactivity of laser-excited Ca+* ions in 3 2DJ (J = 3/2, 5/2) states with neutral H2O molecules was experimentally investigated. The reaction-product ions were sympathetically cooled by laser-cooled 40Ca+ ions and detected by laser-induced fluorescence mass spectroscopy. The reaction rate coefficient of Ca+*(DJ) + H2O → products was found to be 1.8(1) × 103 s−1 Pa−1 at an ion temperature of T = 3.1(1) × 103 K. The ion temperature dependence of the reaction rate coefficient was also measured for buffer-gas-cooled Ca+ ions.