title: Improved DFT-based interpretation of ESI-MS of aqueous metal cations.
abstract: We present results showing that our recently developed density functional theory (DFT)-based speciation model of the aqueous Al(3+) system has the potential to improve the interpretations of ESI-MS studies of aqueous metal cation hydrolytic speciation. The main advantages of our method are that (1) it allows for the calculation of the relative abundance of a given species which may be directly assigned to the signal intensity in a mass spectrum; (2) in cases where species with identical m⁄z ratios may coexist, the assignment can be unambiguously assigned based on their theoretical relative abundances. As a demonstration of its application, we study four pairs of monomer and dimer aqueous Al(3+) species, each with identical m/z ratio. For some of these pairs our method predicts that the dominant species changes from the monomer to the dimer species under varying pH conditions.
authors.affiliation: Eenheid Algemene Chemie, Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, 1050, Brussels, Belgium. sbogatko@vub.ac.be
authors.forename: Stuart
authors.initials: S
authors.lastname: Bogatko
authors.forename: Emilie
authors.initials: E
authors.lastname: Cauët
authors.forename: Paul
authors.initials: P
authors.lastname: Geerlings