Anionic Oligomerization of Li2[B12H12] and Li[CB11H12]: An Experimental and Computational Study

We present an experimental and computational study of the oligomerization in icosahedral closo-(car)boranes Li-2[B12H12] (I) and Li[CB11H12] (II). The experiments were performed on a hybrid ESI-TQ-FT-ICR mass spectrometer equipped with a 7.0 T superconducting magnet. The computational study consisted of finding energy minimum structures for the molecules I, II and the derived anions [B12H12](2-), [CB11H12](-), [I-2-Li](-), and [II2-Li](-), as well as an estimate for the dissociation energy in the processes [X-2-Li](-) -> X + [X-Li](-) with X = I, II. Comparison of experiments and computations shows an excellent agreement for the bond dissociation energy in the process [II2-Li](-) -> II + [II-Li](-) with Delta E = 1.5 eV.