Water-catalyzed mechanism for the pyrolysis of formic acid

The water-catalyzed mechanism for the pyrolysis of formic acid was studied by the ab initio quantum chemical calculations. The dehydration and decarbo xylation reactions of formic acid occur via five- and six-member-ring hydro gen bonding complexes and transition states, respectively. The role of the water molecule is to serve as a proton relay acting simultaneously as a hyd rogen-atom donor and acceptor. The corresponding potential energy surface w as obtained at G2(MP2) level of theory. The large scatter in the reported e xperimental activation barriers for the dehydration and decarboxylation rea ction of formic acid was explained reasonably. (C) 1999 Elsevier Science B. V. All rights reserved.