Determination of the Kinetic Characteristics of Thermal Desorption and Heterogeneous Reaction of Dissociation of Morphine Molecules on the Surface of Oxidized Tungsten

Under the same experimental conditions the processes of adsorption, heterogenous reaction of dissociation on the surface and thermodesorption of C₁₇H₁₉NO₃ morphine molecules with m/z 285 Da on the surface of oxidized tungsten was studied by the non-stationary such as voltage modulation and flux modulation methods. The experiments were carried out on a high-vacuum mass-spectrometer, in which a “black chamber” was used, all walls of which are cooled with liquid nitrogen. The kinetic characteristics of the processes of thermal desorption and the heterogeneous reaction of dissociation of molecules on the surface such as the rate constant of thermal desorption in the ionic and neutral states K⁺ and K⁰, the corresponding activation energies of thermal desorption E⁺ and E⁰, the pre-exponential factors C and D, as well as the rate constant of the heterogeneous dissociation reaction K^d and the activation energy of the heterogeneous reaction dissociations on the surface, exponential factors in the equation of continuity of the surface concentration for C₉H₇N⁺CH₃ radicals with m/z 144 during the adsorption of morphine molecules on the surface of oxidized tungsten were determined.