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Towards a working density-functional theory for polymers: First-principles determination of the polyethylene crystal structure

Jesper Kleis·Bengt I. Lundqvist·David C. Langreth·Elsebeth Schroder
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Abstract

Equilibrium polyethylene crystal structure, cohesive energy, and elastic constants are calculated by density-functional theory applied with a recently proposed density functional (vdW-DF) for general geometries [Phys. Rev. Lett. 92, 246401 (2004)] and with a pseudopotential-planewave scheme. The vdW-DF with its account for the long-ranged van der Waals interactions gives not only a stabilized crystal structure but also values of the calculated lattice parameters and elastic constants in quite good agreement with experimental data, giving promise for successful application to a wider range of polymers.

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Jesper Kleis, Bengt I. Lundqvist, David C. Langreth, Elsebeth Schroder. 2006-11-19. Towards a working density-functional theory for polymers: First-principles determination of the polyethylene crystal structure. https://doi.org/10.1103/physrevb.76.100201

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