2000/11/22 by Luca Bertini, Dario Bressanini, Massimo Mella +1 · 1 citation
Mathematics · Physics and Astronomy · #Advanced Chemical Physics Studies #Atomic and Molecular Physics #Cold Atom Physics and Bose-Einstein Condensates #Excited state #Mathematics #Monte Carlo method #Physics #Quantum Monte Carlo #Quantum mechanics #Statistics #Wave function #physics.atom-ph #physics.chem-ph #physics.comp-ph
paper · pdf · doi:10.1088/0953-4075/34/3/304
19 pages, no figures, submitted to J. Phys. B
arxiv created 2000/11/22 · openalex publication_date 2001/01/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a new form of explicitly correlated wavefunction whose parameters are mainly linear, to circumvent the problem of the optimization of a large number of nonlinear parameters usually encountered with basis sets of explicitly correlated wavefunctions. With this trial wavefunction we have succeeded in minimizing the energy instead of the variance of the local energy, as is more common in quantum Monte Carlo methods. We have applied this wavefunction to the calculation of the energies of Be 3 P (1s 2 2p 2 ) and Be - 4 S o (1s 2 2p 3 ) by variational and diffusion Monte Carlo methods. The results compare favourably with those obtained by different types of explicitly correlated trial wavefunction already described in the literature. The energies obtained are improved with respect to the best variational ones found in the literature, and within one standard deviation of the estimated non-relativistic limits.