OH RADICAL REACTION-RATE CONSTANTS FOR POLYCYCLIC ALKANES - EFFECTS OF RING STRAIN AND CONSEQUENCES FOR ESTIMATION METHODS

Using a relative rate method, rate constants for the gas-phase reactions of the OH radical with trans-pinane [(1R,2R)-2, 6, 6-trimethylbicyclo[3.1.1]heptane], tricyclene (1, 7, 7-trimethyltricyclo[2.2.1.0(2,6)]heptane), and quadricyclane (quadricyclo-[2.2.1.0(2,6).0(3,5)]heptane) of (1.34 +/- 0.29) X 10(-11) cm3 molecule-1 s-1, (2.86 +/- 0.62) X 10(-12) cm3 molecule-1 s-1 and (1.83 +/- 0.41) X 10(-12) cm3 molecule-1 s-1, respectively, have been determined at 296 +/- 2 K. These rate constants are compared with values calculated from an empirical estimation method and used to refine this estimation technique for the calculation of OH radical reaction rate constants for polycyclic systems.