ABSTRACT
By taking into account the Coulomb and Breit interactions between the electrons, we carried out self-consistent Hartree-Fock calculations of the energy levels in randomly-shaped jellium clusters with up to 276 electrons. The level spacing statistics is found to differ qualitatively from the Wigner distribution and better correspond with the Poisson distribution. Prediction of significantly enhanced farinfrared absorption is in excellent accord with experimental observations. Breit interaction is identified as key to the semi-metallic behavior persistent in small metal clusters at energy scales much lower than the average level spacing.
