Fermi surface topology of LaFePO, LiFeP and LiFeAs

We performed charge self-consistent LDA+DMFT (density functional theory combined with dynamical mean field theory) calculations to study correlation effects on the Fermi surfaces of the iron pnictide superconductors LaFePO, LiFeP an LiFeAs. We find a distinctive change in the topology of the Fermi surface in LaFePO and LiFeP where a hole pocket with Fe dz$^2$ orbital character changes its geometry from a closed shape in LDA to an open shape upon inclusion of correlations. In LiFeAs correlations influence mostly the shape of the hole pockets. We discuss our results in the context of angle-resolved photoemission spectroscopy and de Haas van Alphen observations.