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arXiv · 1106.4830

vdW-DF Study of energetic, structural, and vibrational properties of small water clusters and ice Ih

Brian Kolb·T. Thonhauser
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Abstract

We present results for a density functional theory study of small water clusters and hexagonal ice Ih, using the van der Waals density functional (vdW-DF). In particular, we examine energetic, structural, and vibrational properties of these systems. Our results exhibit excellent agreement with both experiment and quantum-chemistry calculations and show a systematic and consistent improvement over standard exchange-correlation functionals---making vdW-DF a promising candidate for resolving longstanding difficulties with density functional theory in describing water. In addition, by comparing our vdW-DF results with quantum-chemistry calculations and other standard exchange-correlation functionals, we shed light on the question of why standard functionals often fail to describe these systems accurately.

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Brian Kolb, T. Thonhauser. 2011-06-23. vdW-DF Study of energetic, structural, and vibrational properties of small water clusters and ice Ih. https://doi.org/10.1103/physrevb.84.045116

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