Gas phase reactions of La⁺ with acetone: A density functional theory investigation

Abstract

The gas phase reaction of La⁺ cation with acetone is investigated using density functional theory. Both ground and excited state potential energy surfaces are investigated in detail. The present results show that the title reaction starts with the formation of an O-attached complex (IM0). All possible pathways starting with C−O, C−H, and C−C activation have been searched. These reactions can lead to four different products, (¹LaO⁺+C₃H₆, ²LaCH₂COCH₃⁺+H, ¹LaCOCH₂⁺+CH₄and¹LaCH₂⁺+CH₃CHO). The minimum energy reaction path is found to involve spin inversion after IM0 formation, and this potential energy curve-crossing dramatically affects the reaction exothermic. As all the triplet intermediates, transition states and products involved in the reaction lie below the ground reactants (³La⁺+ CH₃COCH₃) after IM0 formation, the reaction is expected to occur spontaneously over the singlet potential energy surface. The present results may be helpful in understanding the mechanism of the title reaction and further experimental investigation of the reaction.