title: Design of neutral Lewis superacids of group 13 elements.
abstract: A general approach toward superstrong neutral Lewis acids, featuring both the pyramidalization of acceptor molecules and the introduction of electron-withdrawing substituents, is proposed and examined theoretically. Complexes of group 13 element derivatives with ammonia at the B3LYP and MP2 levels of theory with def2-TZVPP basis set are considered as examples. Pyramidalization of the acceptor molecule significantly increases its Lewis acidity (by 50-60 kJ mol(-1) for aluminum and gallium compounds and by 120-130 kJ mol(-1) for boron compounds). An additional increase of the complex stability of 55-75 kJ mol(-1) may be achieved by fluorination. The combined increase of the bond dissociation energy amounts to 110-190 kJ mol(-1), which is equivalent to 19-33 orders of magnitude in Lewis acidity.
authors.affiliation: Inorganic Chemistry Group, Department of Chemistry, St. Petersburg State University, University Pr. 26, Old Peterhof 198504, Russia.
authors.forename: Leonie Anna
authors.initials: LA
authors.lastname: Mück
authors.forename: Alexey Y
authors.initials: AY
authors.lastname: Timoshkin
authors.forename: Gernot
authors.initials: G
authors.lastname: Frenking