Tensor factorizations of local second-order Møller–Plesset theory

Jun Yang, Yuki Kurashige, Frederick R. Manby, Garnet K. L. Chan
2011 Journal of Chemical Physics  
Efficient electronic structure methods can be built around efficient tensor representations of the wavefunction. Here we describe a general view of tensor factorization for the compact representation of electronic wavefunctions. We use these ideas to construct low-complexity representations 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
more » ... proximation. 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 favourable accuracy and computational times, while yielding smooth potential energy curves.
doi:10.1063/1.3528935 pmid:21280703 fatcat:zc6z5atwgjfcdcw5zh2xitdx44