Beyond the time‐dependent Hartree grid approximation for curve‐crossing problems
نویسندگان
چکیده
منابع مشابه
A simple approximation beyond Hartree - Fock
The form of a real AT-body fermion wave function when expanded in Slater determinants of natural orbitals is investigated using a computer. I t is found that in the case when the number of natural orbitals is N f 2 there is a considerable reduction in the number of Slater determinants required. This offers the possibility of calculating atomic wave functions which are significantly more accurat...
متن کاملThe diagonal Born–Oppenheimer correction beyond the Hartree–Fock approximation
We report on evaluation of the diagonal Born–Oppenheimer correction ~DBOC! to the electronic energy with Hartree–Fock ~HF! and conventional correlated wave functions for general molecular systems. Convergence of both HF and configuration interaction ~CI! DBOC with the one-particle basis seems to be rather fast, with triple-z quality correlation consistent sets of Dunning et al. sufficiently com...
متن کاملHartree-fock approximation for inverse many-body problems
A new method is presented to reconstruct the potential of a quantum mechanical many-body system from observational data, combining a nonparametric Bayesian approach with a Hartree-Fock approximation. A priori information is implemented as a stochastic process, defined on the space of potentials. The method is computationally feasible and provides a general framework to treat inverse problems fo...
متن کاملRandom Walk Beyond Hartree - Fock
We give a brief discussion of the recently developed Constrained-Path Monte Carlo Method. This method is a quantum Monte Carlo technique that eliminates the fermion sign problem plaguing simulations of systems of interacting electrons. The elimination is accomplished by trading an exact procedure for an approximate one that has been demonstrated to give very accurate estimates of energies and m...
متن کاملGaussian phase-space representation of fermion dynamics: Beyond the time-dependent Hartree-Fock approximation
A Gaussian operator representation for the many-body density matrix of fermionic systems, developed by Corney and Drummond Phys. Rev. Lett. 93, 260401 2004 , is used to derive approximate decoupling schemes for their dynamics. In this approach the reduced single electron density-matrix elements serve as stochastic variables which satisfy an exact Fokker-Planck equation. The number of variables ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Journal of Chemical Physics
سال: 1992
ISSN: 0021-9606,1089-7690
DOI: 10.1063/1.461914