||Second-order Moller-Plesset perturbation (MP2) theory at finite temperature: relation with Surjan's density matrix MP2 and its application to linear-scaling divide-and-conquer method
Kobayashi, MasatoTaketsugu, Tetsuya
Theoretical chemistry accounts
, p.107 , 2015-08-16 , Springer
In 2005, Surjan showed two explicit formulas for evaluating the second-order Moller-Plesset perturbation (MP2) energy as a functional of the Hartree-Fock density matrix D (Chem Phys Lett 406: 318, 2005), which are referred to as the Delta E-MP2[D] functionals. In this paper, we present the finite-temperature (FT) MP2 energy functionals of the FT Hartree-Fock density matrix. There are also two formulas for the FT-MP2, namely the conventional and renormalized ones; the latter of which has recently been formulated by Hirata and He (J Chem Phys 138: 204112, 2013). We proved that there exists one-to-one correspondence between the formulas of two FT-MP2 and the Delta E-MP2[D] functionals. This fact can explain the different behavior of two Delta E-MP2[D] functionals when an approximate Hartree-Fock density matrix is applied, which was previously investigated by Kobayashi and Nakai (Chem Phys Lett 420: 250, 2006). We also applied the FT-MP2 formalisms to the linear-scaling divide-and-conquer method for improving the accuracy with tiny addition of the computational efforts.