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DOE OSTI · 1907335

Massively parallel quantum chemical density matrix renormalization group method

Brabec, Jiri·Brandejs, Jan·Kowalski, Karol·Xantheas, Sotiris·Legeza, Örs·Veis, Libor
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Abstract

Here, we present, to the best of our knowledge, the first attempt to exploit the supercomputer platform for quantum chemical density matrix renormalization group (QCDMRG) calculations. We have developed the parallel scheme based on the in-house MPI global memory library, which combines operator and symmetry sector parallelisms, and tested its performance on three different molecules, all typical candidates for QC-DMRG calculations. In case of the largest calculation, which is the nitrogenase FeMo cofactor cluster with the active space comprising 113 electrons in 76 orbitals and bond dimension equal to 6000, our parallel approach scales up to approximately 2000 CPU cores.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDMRGMPImassive parallelizationquantum chemistrystrong correlation

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Brabec, Jiri, Brandejs, Jan, Kowalski, Karol, Xantheas, Sotiris, Legeza, Örs, Veis, Libor. 2020-12-30. Massively parallel quantum chemical density matrix renormalization group method. https://doi.org/10.1002/jcc.26476

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