Theory of the solid-state physics on the turn: II. Importance of the spin-orbit coupling for 3d-ion compounds: the case of NiO

Abstract

The orbital and spin moment of the Ni2+ ion in NiO has been calculated at 0 K to be 0.54mB and 1.99 mB respectively. Such large orbital moment, more than 20% of the total moment of 2.53 mB, proves the need for the ''unquenching'' of the orbital moment in compounds containing 3d ions. It turns out that the spin-orbit coupling is indispensable for description of magnetic and electronic properties of 3d-ion compounds. These two findings, largely ignored at the nowadays in-fashion solid-state thories, call for an advanced solid-state physics theory.