A very short uranium-uranium bond: the predicted metastable U(2)2+.
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 A, compared to 2.43 A in neutral U2. The Coulomb explosion to 2 U+ lowers the energy by only 1.6 eV and is separated by a broad barrier.
Gagliardi
Laura
L
Dipartimento di Chimica Fisica F. Accascina, Università degli Studi di Palermo, Viale delle Scienze-Parco d'Orleans II, Palermo, Italy. laura.gagliardi@unipa.it
Pyykkö
Pekka
P
Roos
Björn O
BO