Using first principles theory based on density functional formulation we have studied the interactions of uranium atom with tetraketone complexes used for all-uranium redox flow battery. The geometry and electronic structures are studied in detail. We found that uranium atom interacts strongly with tetraketone complexes, the interaction energy is more than 7.0 eV, and uranium atom acts as an electron acceptor with about 0.6 electrons transferred from tetraketone complexes, while uranium atom carries the magnetic moment of 2 mu(B) (c) 2005 Elsevier B.V. All rights reserved.