The project based on work by Darensbourg and cowokers involves gaining a complete understanding of the cis to trans isomerization of the Mo(CO)4(PR3)2 (R Et n-butyl) complex. The cis complex is syntesized and the thermodynamics kinetics and mechanism of the isomerization reaction are studied. Activision enthalpies obatained from the kinetics studies are then related to the overall reaction enthakpy determination by studying the equilibrium constant of the isomerization reaction at several temperatures. The results serve to illustrate the important relationship between thermodynamics and chemical kinetics.