oregonator Paul Cochrane Example simulation of the Oregonator model of oscillating chemical kinetics equations. Calculates concentrations of components participating in the Oregonator model. The reaction scheme is A + Y ----> X + R (1) X + Y ----> 2 R (2) A + X ----> 2 X + 2 Z (3) 2 X ----> A + R (4) B + Z ----> 1/2 Y (5) Rate laws are d[X]/dt = k1 [A] [Y] - k2 [X] [Y] + k3 [A] [X] - 2 k4 [X]^2 d[Y]/dt = -k1 [A] [Y] - k2 [X] [Y] + (1/2) k5 [B] [Z] d[Z]/dt = 2 k3 [A] [X] - k5 [B] [Z] which are transformed to d[X]_d(tau) = (k1 [A] [Y] - k2 [X] [Y] + k3 [A] [X] - 2 k4 [X]^2)/(k5 [B]) d[Y]_d(tau) = (-k1 [A] [Y] - k2 [X] [Y] + (1/2) k5 [B] [Z])/(k5 [B]) d[Z]_d(tau) = (2 k3 [A] [X] - k5 [B] [Z])/(k5 [B]) where tau = k5*[B]*t is a unitless time variable. The program integrates these equations, assuming that concentrations of A and B are constant. Adapted for xmds from "Mathematica computer programs for physical chemistry", William H. Cropper, Springer Verlag (1998) tau yes yes yes yes main 1 main double CX CY CZ RK4IP 50 5000 500 main 500 X X10 Y Z