Fixed-node diffusion Monte Carlo computations for closed-shell jellium spheres

Physical Review B, 1996

Physical Review B, 2011

Cornell University - arXiv, 2020

Journal of Molecular Structure: THEOCHEM, 1997

Physical Review B, 2012

Physical Review B - PHYS REV B, 2006

We study the ground state properties of a quasi-one-dimensional electron gas interacting via an effective potential with a harmonic transversal confinement and long-range Coulomb tail. The exact correlation energy has been calculated for a wide range of electron densities by using the lattice regularized diffusion Monte Carlo method, which is a recent development of the standard projection Monte Carlo technique. In this case it is particularly useful as it allows one to sample the exact ground state of the system, even in the low-density regime when the exchange between electrons is extremely small. For different values of the width parameter b (0.1a0*<=b<=4a0*) , we give a simple parametrization of the correlation energy, which provides an accurate local density energy functional for quasi-one-dimensional systems. Moreover, we show that static correlations are in qualitative agreement with those obtained for the Luttinger liquid model with long-range interactions.

2008

Physical Review B, 2011

The Journal of chemical physics, 2015

We revisit the Hartree-Fock (HF) calculation for the uniform electron gas, or jellium model, whose predictions-divergent derivative of the energy dispersion relation and vanishing density of states (DOS) at the Fermi level-are in qualitative disagreement with experimental evidence for simple metals. Currently, this qualitative failure is attributed to the lack of screening in the HF equations. Employing Slater's hyper-Hartree-Fock (HHF) equations, derived variationally, to study the ground state and the excited states of jellium, we find that the divergent derivative of the energy dispersion relation and the zero in the DOS are still present, but shifted from the Fermi wavevector and energy of jellium to the boundary between the set of variationally optimised and unoptimised HHF orbitals. The location of this boundary is not fixed, but it can be chosen to lie at arbitrarily high values of wavevector and energy, well clear from the Fermi level of jellium. We conclude that, rather...

Introduction and Mathematical Analysis to Heat Transfer by Condensation, 2024

Condensation represents the change of phase from the vapor state to the liquid state because of cooling. It is considered one of the most important heat-transfer processes in many energyconversion systems, such as electric power generation plants. Condensation heat transfer finds its applications in power generation, refrigeration, air conditioning, thermal management, and nature in general. When the temperature of vapor is reduced below the saturation temperature, condensation occurs, e.g., when vapor is in contact with a cool surface. Film wise and dropwise condensation are the two most commonly studied forms of condensation. In both these modes, the formed condensate offers a significant thermal resistance between the cooler surface and the vapor, and this resistance increases with the condensate thickness. Hence, dropwise condensation has higher heat transfer in comparison to film wise condensation.