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arXiv · 1512.07236

Generalized canonical purification for density matrix minimization

Lionel A. Truflandier·Rivo M. Dianzinga·David R. Bowler
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Abstract

A Lagrangian formulation for the constrained search for the $N$-representable one-particle density matrix based on the McWeeny idempotency error minimization is proposed, which converges systematically to the ground state. A closed form of the canonical purification is derived for which no a posteriori adjustement on the trace of the density matrix is needed. The relationship with comparable methods are discussed, showing their possible generalization through the hole-particle duality. The appealing simplicity of this self-consistent recursion relation along with its low computational complexity could prove useful as an alternative to diagonalization in solving dense and sparse matrix eigenvalue problems.

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BibTeXRIS

Lionel A. Truflandier, Rivo M. Dianzinga, David R. Bowler. 2016-01-05. Generalized canonical purification for density matrix minimization. https://doi.org/10.1063/1.4943213

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