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تسجيل مستخدم جديدFully self-consistent optimization of the Jastrow-Slater-type wave function using a similarity-transformed Hamiltonian
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Masayuki Ochi
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For highly accurate electronic structure calculation, the Jastrow correlation factor is known to successfully capture the electron correlation effects. Thus, the efficient optimization of the many-body wave function including the Jastrow correlation factor is of great importance. For this purpose, the transcorrelated $+$ variational Monte Carlo (TC$+$VMC) method is one of the promising methods, where the one-electron orbitals in the Slater determinant and the Jastrow factor are self-consistently optimized in the TC and VMC methods, respectively. In particular, the TC method is based on similarity-transformation of the Hamitonian by the jastrow factor, which enables efficient optimization of the one-electron orbitals under the effective interactions. In this study, by test calculation of a helium atom, we find that the total energy is systematically improved by using better Jastrow functions, which can be naturally understood by considering a role of the Jastrow factor and the effective potential introduced by the similarity-transformation. We also find that one can partially receive a benefit of the orbital optimization even by one-shot TC$+$VMC, where the Jastrow parameters are optimized at the Hartree-Fock$+$VMC level, while a quality of the many-body wave function is inferior to that for self-consistent TC$+$VMC. A difference between TC and biorthogonal TC is also discussed. Our study provides important knowledge for optimizing many-body wave function including the Jastrow correlation factor, which would be of great help for development of highly accurate electronic structure calculation.
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