2010/08/29 by Jun Yang, Yuki Kurashige, Frederick R. Manby +2
Chemistry · Mathematics · Physics and Astronomy · #Advanced Chemical Physics Studies #Advanced NMR Techniques and Applications #Algorithm #Ansatz #Atomic orbital #Electron #Factorization #Geometry #Mathematics #Perturbation theory (quantum mechanics) #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Representation (politics) #Statistical physics #Tensor (intrinsic definition) #Wave function #physics.comp-ph #quant-ph
paper · pdf · doi:10.1063/1.3528935
arxiv created 2010/08/29 · openalex publication_date 2011/01/27 · arxiv updated 2015/05/19 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/06
Efficient electronic structure methods can be built around efficient tensor representations of the wavefunction. Here we first describe a general view of tensor factorization for the compact representation of electronic wavefunctions. Next, we use this language to construct a low-complexity representation of the doubles amplitudes in local second-order Møller-Plesset perturbation theory. We introduce two approximations--the direct orbital-specific virtual approximation and the full orbital-specific virtual approximation. In these approximations, each occupied orbital is associated with a small set of correlating virtual orbitals. Conceptually, the representation lies between the projected atomic orbital representation in Pulay-Saebø local correlation theories and pair natural orbital correlation theories. We have tested the orbital-specific virtual approximations on a variety of systems and properties including total energies, reaction energies, and potential energy curves. Compared to the Pulay-Saebø ansatz, we find that these approximations exhibit favorable accuracy and computational times while yielding smooth potential energy curves.