A catal
ytic s
ystem consisting of tungsten carbene generated from WCl
6 and an atomic carbon is investigated theoreticall
y for the metathesis of 1-octene at B3LYP/extended LANL2DZ level of DFT. The ground-state geometries and charge distributions of the structures belonging to the reaction mechanism are located. Energetics for the complete set of reactions, involving the formation of the tungsten carbene precatal
yst, Cl
4W
CCl
2, the formation of tungsten meth
ylidene and tungsten hept
ylidene with this precatal
yst, and finall
y productive and degenerative metathesis steps with these alk
ylidene species are calculated in terms of total electronic energ
y and thermal energies. The free-energ
y (Δ
G298) surfaces of the structures involved in the related reactions are constructed. In addition, solvent effects on the single point energies of the structures are investigated for two different solvents, namel
y, c
yclohexane and chloroform. The results indicate that the formation of the catal
yticall
y active hept
ylidene is energeticall
y favored in comparison to the formation of meth
ylidene, while the degenerative and productive metathesis steps are competitive. In the catal
ytic c
ycle, the formation of eth
ylene is exothermic, while the formation of 7-tetradecene is endothermic. As expected, solvent effects on the metathesis reactions are minor and solvation does not cause an
y change in the directions of the overall metathesis reactions.