From OBeHe to H3BOBeHe:: Enhancing the stability of a neutral helium compound

According to MP2, CCD, and CCSD(T) calculations, H3BOBeHe ((1)A(1)) is a helium compound potentially observable as a metastable species. In fact, it is stable with respect to He and BH3 detachment, and is separated by a barrier of ca. 3 kcal mol(-1) from the more stable H2B-O-BeH and He. In addition, its He detachment energy of nearly 5-6 kcal mol(-1) is almost twice that of OBeHe. This suggests that, using suited neutral Lewis acids, an otherwise poor helium acceptor could be activated so to fix the lightest noble gas. Confirming this prediction is a challenge for future 'computational experiments'. (c) 2005 Elsevier B.V. All rights reserved.