Relativistic Pseudopotential ab initio Study of Electronic Structure in Uranyl Cations

Geometry and electronic structure of uranyl cations have been calculated with harmonic vibration analysis, using relativistic effective core pseudopotential （RECP） method. The calculable bond lengthes and vibrational frequencies have compared favorably with experimental value. U5f-O2p bond dominates in the U-O bonding, while there are strong bonds between U6p, U6d, U7s and d-s hybridizing orbitals with O2s aloud orbital. The calculated results with dif- ferent spin multiplicity show that the ground state of UO₂²⁺ prefer ¹∑_g⁺.