Hydrogen bonding characterization in water and small molecules

Abstract

The prototypical Hydrogen bond in water dimer and Hydrogen bonds in the protonated water dimer, in other small molecules, in water cyclic clusters, and in ice, covering a wide range of bond strengths, are theoretically investigated by first-principles calculations based on the Density Functional Theory, considering a standard Generalized Gradient Approximation functional but also, for the water dimer, hybrid and van-der-Waals corrected functionals. We compute structural, energetic, and electrostatic (induced molecular dipole moments) properties. In particular, Hydrogen bonds are characterized in terms of differential electron densities distributions and profiles, and of the shifts of the centres of Maximally localized Wannier Functions. The information from the latter quantities can be conveyed into a single geometric bonding parameter that appears to be correlated to the Mayer bond order parameter and can be taken as an estimate of the covalent contribution to the Hydrogen bond. By considering the cyclic water hexamer and the hexagonal phase of ice we also elucidate the importance of cooperative/anticooperative effects in Hydrogen-bonding formation.

11 figures

References in corpus (7)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• On the accuracy of DFT exchange-correlation functionals for H bonds in small water clusters II: The water hexamer and van der Waals interactions
• On how good DFT exchange-correlation functionals are for H bonds in small water clusters: Benchmarks approaching the complete basis set limit
• Van der Waals interactions in DFT made easy by Wannier functions
• van der Waals density functionals built upon the electron-gas tradition: Facing the challenge of competing interactions
• Covalent features in the hydrogen bond of a water dimer: molecular orbital analysis
• Electron Delocalization Determined Anomalous Stability in Small Water Rings