The second major aim of this work is to understand the antioxidant mechanisms of the diphenylamines. The potential energy surfaces (PES) of reactions between the substituted diphenylamines with CH3OO• radical were calculated at M05-2X/6-311++G(d,p) level of theory. Rate constants for hydrogen atom transfer processes at the N H bond were also computed at the same level of theory using the conventional transition state theory (TST). |