Theoretical study of H sub 2 elimination from B sub 4 H sub 10 , B sub 5 H sub 11 , and B sub 6 H sub 12 and BH sub 3 elimination from B sub 4 H sub 10
- Auburn Univ., AL (USA)
Ab initio calculations are employed to evaluate decomposition pathways of several boron hydrides. Reactants, products, and transition states for the decomposition of B{sub 4}H{sub 10} were optimized at the MP2/6-31G* level. The predicted barrier for formation of B{sub 4}H{sub 8} + H{sub 2} is in good agreement with experiment (26.8 (calcd) and 23.7 (exptl) kcal/mol) while the barrier for formation of B{sub 3}H{sub 7} + BH{sub 3} is 13.7 kcal/mol higher. Loss of H{sub 2} from B{sub 5}H{sub 11} and B{sub 6}H{sub 12} is predicted to occur with activation barriers of 52.8 and 37.4 kcal/mol, respectively (MP2/6-31G*//3-21G). The most significant discovery is that the observed decomposition of B{sub 5}H{sub 11} cannot occur as previously thought by the reaction B{sub 5}H{sub 11} {yields} B{sub 4}H{sub 8} + BH{sub 3} since this reaction has a calculated endothermicity 18.1 kcal/mol greater than the observed activation barrier.
- OSTI ID:
- 5362123
- Journal Information:
- Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 112:19; ISSN 0002-7863; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
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