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arXiv · 1701.01568

Linear-scaling electronic structure theory: Electronic temperature in the Kernel Polynomial Method

Eunan J. McEniry·Ralf Drautz
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Abstract

Linear-scaling electronic structure methods based on the calculation of moments of the underlying electronic Hamiltonian offer a computationally efficient and numerically robust scheme to drive large-scale atomistic simulations, in which the quantum-mechanical nature of the electrons is explicitly taken into account. We compare the kernel polynomial method to the Fermi operator expansion method and establish a formal connection between the two approaches. We show that the convolution of the kernel polynomial method may be understood as an effective electron temperature. The results of a number of possible kernels are formally examined, and then applied to a representative tight-binding model.

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Eunan J. McEniry, Ralf Drautz. 2017-01-06. Linear-scaling electronic structure theory: Electronic temperature in the Kernel Polynomial Method. https://arxiv.org/abs/1701.01568

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