A very short uranium-uranium bond: The predicted metastable U-2(2+)

摘要

Quantum chemical calculations, based on multiconfigurational wave functions and including relativistic effects, show that the U-2(2+) system has a large number of low-lying electronic states with S of 0 to 2 and Lambda ranging from zero to ten. These states share a very small bond length of about 2.30 angstrom, compared to 2.43 angstrom in neutral U-2. The Coulomb explosion to 2 U+ lowers the energy by only 1.6 eV and is separated by a broad barrier.