A van der Waals density functional study of ice Ih
1WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. ikutaro@wpi-aimr.tohoku.ac.jp
The Journal of Chemical Physics
|December 15, 2010
Summary
Density functional theory using van der Waals density functional (vdW-DF) accurately predicts binding energy for ice Ih. This method improves upon standard approximations for describing water ice structures and properties.
Area of Science:
- Computational physics and chemistry
- Materials science
- Condensed matter physics
Background:
- Accurate theoretical modeling of water ice (ice Ih) is crucial for understanding its properties.
- Standard approximations in density functional theory often struggle to capture the nuances of hydrogen-bonded systems like ice.
Purpose of the Study:
- To investigate the efficacy of van der Waals density functional (vdW-DF) for calculating the structural and energetic properties of ice Ih.
- To assess the impact of nonlocal correlation (van der Waals interaction) on the description of water ice.
Main Methods:
- Employing density functional theory (DFT) with the vdW-DF.
- Calculating equilibrium crystal structure, binding energy, and bulk modulus for ice Ih.
- Comparing results with high-level quantum chemistry calculations and experimental data.
Main Results:
- vdW-DF overestimates the equilibrium volume of ice Ih.
- vdW-DF accurately predicts the binding energy of ice Ih.
- The inclusion of van der Waals interactions offers a significant improvement over standard generalized gradient approximations.
Conclusions:
- vdW-DF provides a more accurate description of ice Ih compared to standard DFT approximations.
- Van der Waals interactions are essential for accurately modeling the properties of water ice.
- This approach enhances the reliability of theoretical predictions for hydrogen-bonded materials.
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