Molecules and Ions at Very Low Temperatures

Abstract

The generation and study of 'cold' gas-phase molecules characterised by very low translational temperatures T trans ≤ 1 K is an upcoming field of research in physical chemistry which has received considerable attention over the past years. A particular interesting form of cold molecules are ensembles of cold localised cations in ion traps which form ordered structures known as 'Coulomb crystals'. The present article reviews the experimental methods used for the generation of atomic and molecular Coulomb crystals and highlights recent experiments which take advantage of their intriguing properties in order to study chemical reactions at very low temperatures with single-particle sensitivity.

Rovibronic Spectroscopy of Sympathetically Cooled 40CaH+

“…The Coulomb crystals containing mixtures of atomic and molecular ions have structures that can be simulated by molecular dynamics as a method for determining the number of ions in an imaged crystal e.g. in detecting the ions lost in a dissociation measurement [21,22,64]. Molecular ions can be co-trapped and sympathetically cooled in a Coulomb crystal [91].…”