PNNL

Abstract

Carbon dioxide (CO2) was used as a reaction gas to investigate the gas-phase ion-molecule interactions using the Agilent 8900 QQQ-ICP-MS. A solution containing 45 elements representative of the periodic table was used to supply the ions to react with CO2 in the collision/reaction cell (CRC). The only significant product ions formed were monoxides. The general reactivity was shown to be consistent with density functional theory (DFT)-predicted reaction enthalpies, such that all predicted exothermic reactions produced product ions at levels of at least 1% of the unreacted ion. For the most part, endothermic reactions that were observed had sufficient ion kinetic energy to overcome the DFT-predicted reaction enthalpies. Our results suggest that reaction enthalpy is a reasonable predictor of reactivity with CO2 on the timescales of the interactions in non-thermal ICP-MS/MS systems. The ease and rapidity of data collection with the QQQ-ICP-MS and DFT calculations using the NWChem suite has value given the scarcity of thermochemical data of CO2 reactions in the literature. Our data is also especially useful for the identification of targeted reaction chemistries to be leveraged for analytical method development, such as for the inline separation of isobaric interferences from analytes of interest.