2020/11/16 by Tina N. Mihm, William Z. Van Benschoten, James J. Shepherd · 7 citations
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Advanced Physical and Chemical Molecular Interactions #Cluster (spacecraft) #Convergence (economics) #Coupled cluster #Monte Carlo method #Perturbation theory (quantum mechanics) #Quantum Monte Carlo #Quantum, superfluid, helium dynamics #Twist #cond-mat.quant-gas #physics.chem-ph
paper · pdf · doi:10.1063/5.0033408
published in The Journal of Chemical Physics 154(2), 024113 (American Institute of Physics) · 9 figures, 9 pages
arxiv created 2020/11/16 · openalex created_date 2020/11/23 · openalex publication_date 2021/01/12 · arxiv updated 2021/02/03 · openalex updated_date 2026/08/05
We recently developed a scheme to use low-cost calculations to find a single twist angle where the coupled cluster doubles energy of a single calculation matches the twist-averaged coupled cluster doubles energy in a finite unit cell. We used initiator full configuration interaction quantum Monte Carlo as an example of an exact method beyond coupled cluster doubles theory to show that this selected twist angle approach had comparable accuracy in methods beyond coupled cluster. Furthermore, at least for small system sizes, we show that the same twist angle can also be found by comparing the energy directly (at the level of second-order Moller-Plesset theory), suggesting a route toward twist angle selection, which requires minimal modification to existing codes that can perform twist averaging.