Table 1.

Heats of formation for reactants, complexes, and products for the dehalogenation reaction of DCE by acetate, kcal/mol

Molecule	AM1	AM1-SSP	Target
Reactants
Acetate	−115.47	−122.36	−120.70*
DCE	−33.12	−31.34	−29.98†
Complexes‡
1.9 Å	−135.50	−150.71	−152.36
TS	−135.59	−150.86	−150.15
2.4 Å	−158.56	−164.52	−163.63
2.8 Å	−160.55	−167.18	−167.74
3.0 Å	−159.87	−166.47	−167.26
3.2 Å	−159.00	−165.44	−166.20
4.0 Å	−155.73	−161.39	−161.46
5.0 Å	−153.73	−158.70	−157.58
Products
2-Chloroethylacetate	−110.08	−111.25	−111.12§
Chloride anion	−37.66	−54.93	−54.36¶

^*Ref. 31. 

^†Ref. 32. 

^‡ The heat of formation for these complexes was obtained by adding the ab initio interaction energy for the complex to the experimental heats of formation of acetate and DCE. The first column list the distance between the attacking carboxylate oxygen to the reacting carbon (see Fig. 1A). 

^§The heat of formation was obtained from a CBS4 calculation (Ref. 33). 

^¶Ref. 34.