[en] The effects of secondary ligands on the electronic structure of uranyl, UO₂²⁺, are investigated in a perturbing point ion model, making use of the relativistic Dirac--Slater molecular orbital (MO) approach. Variation of ''crystal-field splittings'' with primary U--O bond length is explored; relaxation of the uranyl MO's is taken into account by self-consistent iterations. The theoretical splittings are found to agree rather well with the x-ray photoemission spectroscopy (XPS) data of Veal et al. Comparison is made with optical data and reasons are given for the poor agreement