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The Hydration Number of Li+ in Liquid Water

Susan B. Rempe·Lawrence R. Pratt·Gerhard Hummer·Joel D. Kress·Richard L. Martin·Antonio Redondo
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Abstract

A theoretical treatment based upon the quasi-chemical theory of solutions predicts the most probable number of water neighbors in the inner shell of a Li+ ion in liquid water to be four. The instability of a six water molecule inner sphere complex relative to four-coordinated structures is confirmed by an `ab initio' molecular dynamics calculation. A classical Monte Carlo simulation equilibrated 26 water molecules with a rigid six-coordinated Li(H2O)6+ complex with periodic boundary conditions in aqueous solution. With that initial configuration for the molecular dynamics, the six-coordinated structure relaxed into four-coordinated arrangements within 112 fs and stabilized. This conclusion differs from prior interpretations of neutron and X-ray scattering results on aqueous solutions.

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Susan B. Rempe, Lawrence R. Pratt, Gerhard Hummer, Joel D. Kress, Richard L. Martin, Antonio Redondo. 2000-01-05. The Hydration Number of Li+ in Liquid Water. https://arxiv.org/abs/physics/0001011

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