Ab initio QM/MM molecular dynamics simulation of preferential K+ solvation in aqueous ammonia solution
Abstract
A combined ab initio quantum mechanical/molecular mechanical (QM/MM) molecular dynamics simulation has been performed to investigate the solvation structure of K+ in 18.4% aqueous ammonia solution. The chemically most relevant region, the first solvation sphere of K+, was treated by Born–Oppenheimer ab initio quantum mechanics using LANL2DZ basis sets, while the rest of the system was described by classical pair potentials. Within the first solvation shell of K+, the QM/MM simulation reveals a polyhedral structure with an average coordination number of 7.6, consisting of 6.7