Abstract
We present a computational strategy to derive the absolute pK11 values of divalent and trivalent metal cations in aqueous solution from computed pK11 changes relative to the measured pK11 of a reference metal. We show that our strategy could yield accurate relative pK11 values, which, in turn, can help to determine key properties of biologically important metal cations in aqueous solution such as the dominant CN of Ca2+ and the CN of the deprotonated Zn2+ hexahydrate. The key factors governing the deprotonation of a metal-bound water molecule were identified.