Distinguished coordinate reaction paths

Distinguished Coordinate and Other Reaction Paths Bifurcations and Other Paths Coordinates and Path-Based Surfaces... 

A. Intrinsic Reaction Paths and Natural Collision Coordinates Variations on the Same Theme Potentials for Distinguished Coordinate Paths IRP Potentials in Internal (Valence) Coordinates Reaction Surfaces V. Dynamics on Path-Based Surfaces... 

PES based on distinguished coordinates or similar reaction surface potentials [70] are directly applicable in Eq. (5.6). For ab initio reaction path potentials, we discussed the conversion of IRP-based potentials to internal coordinates in Section IV. D. Our group has used trajectory studies to follow the decomposition of HCOH, as in Eq. (3.15) [56,57], and the competition between exchange and abstraction reactions such as Eq. (3.14). These studies have used IRP based potentials converted to internal coordinates. 

In developing an ab initio PES for a chemical reaction in terms of a single reaction path potential, we first located the stationary points on the PES, then followed the reaction path by the steepest descent or distinguished coordinate methods, then chose coordinates, natural collision coordinates or internals, and finally expressed the PES as a series expansion about the... 

So Eq. (7.2) is a new type of reaction path potential, with some significant advantages. Natural collision coordinates are not involved, so the PES is well-defined independent of the curvature of the path. For distinguished coordinate paths, the PES of Eq. (4.14) depends critically on that coordinate this is sometimes unreasonable since that may be just one of a number of coordinates that change along the path. Equation... 

---