Grand-Canonical Interpolation Models
Ramón Alain Miranda‐Quintana, Paul W. Ayers · Apple Academic Press eBooks · 2018
62 We analyze the physical grounds of common approaches used to model the dependency of the ground state energy on the number of electrons in molecular systems ( E vs. N models). We elaborate on a recent result indicating that smooth interpolation models are inconsistent with the popular grand ensemble approach to open quantum systems, and we illustrate this discrepancy using the parabolic and exponential E vs. N models. Unlike most previous considerations of this problem, we explicitly account for the possibility of degenerate ground states and nonconvexity of the energy.