2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/170935We claim that for calculations of the electronic structure of 3d oxides very strong electron correlations have to be taken into account similarly to those assumed in many-electron crystal field approach. For Co3+ ions in NaxCoO2.yH2O there are 15 low lying many-electron states within 0.1 eV as can be obtained in the many-electron CEF approach with taking into account the spin-orbit coupling. We claim, that the used by us Hamiltonian for the trigonal distortion is correct.4 pages, 3 fig embededStrongly Correlated Electronstext