Producing H-2 from water is a very challenging task. Using quantum chemical calculations with the MP2 and CCSD(T) methods and the aug-cc-pVnZ basis sets (extrapolated to CBS), we investigated the possibilities of B2H6, AlH3, Al2H6 and AlH3BH3 to act as catalysts in the reactions that split water. Hydrogen production from H2O is greatly accelerated in the presence of alane, dialane or borane- alane in such a way that reaction H2O + Al2H6 is a nearly spontaneous process. The main catalytic effect of AlH3 arises from the occurrence of a strong dihydrogen bond of the type Al-H-delta -H delta+-O within a cyclic transition structure. (C) 2009 Elsevier B. V. All rights reserved.