An effective sub-quadratic scaling atomic-orbital reformulation of the scaled opposite-spin RI-CC2 ground-state model using Cholesky-decomposed densities and an attenuated Coulomb metric

Sacchetta, F.; Graf, D.; Laqua, H.; Ambroise, M. A.; Kussmann, J.; Dreuw, A. and Ochsenfeld, C. (2022): An effective sub-quadratic scaling atomic-orbital reformulation of the scaled opposite-spin RI-CC2 ground-state model using Cholesky-decomposed densities and an attenuated Coulomb metric. In: Journal of Chemical Physics, Vol. 157, No. 10, 104104

Abstract

An atomic-orbital reformulation of the Laplace-transformed scaled opposite-spin (SOS) coupled cluster singles and doubles (CC2) model within the resolution of the identity (RI) approximation (SOS-RI-CC2) is presented that extends its applicability to molecules with several hundreds of atoms and triple-zeta basis sets. We exploit sparse linear algebra and an attenuated Coulomb metric to decrease the disk space demands and the computational efforts. In this way, an effective sub-quadratic computational scaling is achieved with our omega-SOS-CDD-RI-CC2 model. Moreover, Cholesky decomposition of the ground-state one-electron density matrix reduces the prefactor, allowing for an early crossover with the molecular orbital formulation. The accuracy and performance of the presented method are investigated for various molecular systems. Published under an exclusive license by AIP Publishing.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0021-9606
• Language: English