Spin-orbit coupling and k-dependent Zeeman splitting in strontium ruthenate.

We compare the relativistic LDA Fermi surface of Sr2RuO4 to direct experimental evidence of spin-orbit coupling from de Haas-van Alphen experiments. The k-dependence of the Zeeman splitting at the Fermi surface is modelled with a range of tight binding models of the quasi-particle bands. Only a very restricted class of parameters are consistent with evidence from the de Haas-van Alphen experiments for a strong k-dependent Zeeman splitting on the alpha Fermi surface sheet.