Fully self-consistent optimization of the Jastrow-Slater-type wave function using asimilarity-transformed Hamiltonian

 Masayuki Ochi

 

 For highly accurate electronic structure calculation, theJastrow correlation factor is known to suc-cessfully capture the electron correlation effects. Thus, the efficient optimization of the many-bodywave function including the Jastrow correlation factor is of great importance. For this purpose, thetranscorrelated + variational Monte Carlo (TC+VMC) methodis one of the promising methods,where the one-electron orbitals in the Slater determinant and the Jastrow factor are self-consistentlyoptimized in the TC and VMC methods, respectively. In particular, the TC method is based onsimilarity-transformation of the Hamitonian by the jastrow factor, which enables efficient optimiza-tion of the one-electron orbitals under the effective interactions. In this study, by test calculationof a helium atom, we find that the total energy is systematically improved by using better Jastrowfunctions, which can be naturally understood by considering a role of the Jastrow factor and theeffective potential introduced by the similarity-transformation. We also find that one can partiallyreceive a benefit of the orbital optimization even by one-shot TC+VMC, where the Jastrow parame-ters are optimized at the Hartree-Fock+VMC level, while a quality of the many-body wave functionis inferior to that for self-consistent TC+VMC. A differencebetween TC and biorthogonal TC isalso discussed. Our study provides important knowledge foroptimizing many-body wave functionincluding the Jastrow correlation factor, which would be ofgreat help for development of highlyaccurate electronic structure calculation

 

https://arxiv.org/pdf/2109.05803.pdf