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arXiv · 2411.07565

Parallel Multi-Coordinate Descent Methods for Full Configuration Interaction

Yuejia Zhang·Weiguo Gao·Yingzhou Li
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Abstract

We develop a multi-threaded parallel coordinate descent full configuration interaction algorithm (mCDFCI), for the electronic structure ground-state calculation in the configuration interaction framework. The FCI problem is reformulated as an unconstrained minimization problem, and tackled by a modified block coordinate descent method with a deterministic compression strategy. mCDFCI is designed to prioritize determinants based on their importance, with block updates enabling efficient parallelization on shared-memory, multi-core computing infrastructure. We demonstrate the efficiency of the algorithm by computing an accurate benchmark energy for the chromium dimer in the Ahlrichs SV basis (48e, 42o), which explicitly includes $2.07 \times 10^9$ variational determinants. We also provide the binding curve of the nitrogen dimer under the cc-pVQZ basis set (14e, 110o). Benchmarks show up to $79.3\%$ parallel efficiency on 128 cores.

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Yuejia Zhang, Weiguo Gao, Yingzhou Li. 2024-11-12. Parallel Multi-Coordinate Descent Methods for Full Configuration Interaction. https://arxiv.org/abs/2411.07565

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