Classical trajectory calculations on a series of three DIM potential e
nergy surfaces and a standard LEPS surface for the reaction H + F-2 --
> HF + F are reported. All surfaces have the same features in collinea
r configurations but differ in the position, height and number of acce
ssible saddle points in bent configurations. The dependence of reactio
n cross sections, product energy and angular distributions, thermal ra
te data and reaction mechanism on these features is investigated and d
iscussed. The non-collinear part of the surfaces is of particular inte
rest when it allows for microscopic branching, the various ensuing rea
ction mechanisms making different contributions to the product propert
y distributions. In particular, a broadening of the HF vibrational dis
tribution together with the appearance of a component extending to ver
y low vibrational levels can arise from reactive encounters passing th
rough a T-shaped transition state.