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Geometry Optimization of Crystals by the Quasi-Independent Curvilinear Coordinate Approximation

Karoly Nemeth·Matt Challacombe
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Abstract

The quasi-independent curvilinear coordinate approximation (QUICCA) method [K. Németh and M. Challacombe, J. Chem. Phys. {\bf 121}, 2877, (2004)] is extended to the optimization of crystal structures. We demonstrate that QUICCA is valid under periodic boundary conditions, enabling simultaneous relaxation of the lattice and atomic coordinates, as illustrated by tight optimization of polyethylene, hexagonal boron-nitride, a (10,0) carbon-nanotube, hexagonal ice, quartz and sulfur at the $Γ$-point RPBE/STO-3G level of theory.

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Karoly Nemeth, Matt Challacombe. 2005-08-10. Geometry Optimization of Crystals by the Quasi-Independent Curvilinear Coordinate Approximation. https://doi.org/10.1063/1.2121569

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