Collins, ScottHasan, GalibJoshi, AnujMcIndoe, J. ScottLinnolahti, Mikko2021-08-052021-08-0520212021Collins, S., Hasan, G., Joshi, A., McIndoe, J. S., & Linnolahti, M. (2021). Are Methylaluminoxane Activators Sheets? ChemPhysChem, 22(13), 1326-1335. https://doi.org/10.1002/cphc.202100268.https://doi.org/10.1002/cphc.202100268http://hdl.handle.net/1828/13205Density functional theory calculations on neutral sheet models for methylaluminoxane (MAO) indicate that these structures, containing 5-coordinate and 4-coordinate Al, are likely precursors to ion-pairs seen during the hydrolysis of trimethylaluminum (Me3Al) in the presence of donors such as octamethyltrisiloxane (OMTS). Ionization by both methide ([Me]−) and [Me2Al]+ abstraction, involving this donor, were studied by polarizable continuum model calculations in fluorobenzene (PhF) and o-difluorobenzene (DFB) media. These studies suggest that low MW, 5-coordinate sheets ionize by [Me2Al]+ abstraction, while [Me]− abstraction from Me3Al-OMTS is the likely process for higher MW 4-coordinate sheets. Further, comparison of anion stabilities per mole of aluminoxane repeat unit (MeAlO)n, suggest that anions such as [(MeAlO)7(Me3Al)4Me]−=[7,4]− are especially stable compared to higher homologues, even though their neutral precursors are unstable.enmethylaluminoxaneionizationESI-MSanionizationsheetsUVic Genome BC Proteomics CentreArticleDepartment of Chemistry