Sticking Probabilities of Structural Isomers of Butene under Non-Equilibrium Gas–Surface Collision Conditions

The sticking probabilities of butene structural isomers (cis-2-butene, trans-2-butene, 1-butene) at low and high incident kinetic energies onto their condensed phases were measured via King and Wells mass spectrometry with surface conditions monitored by time-resolved in situ reflection absorption infrared spectroscopy (RAIRS). The sticking probabilities of the three compounds on their respective condensed films agreed with each other, demonstrating that varying the molecular structure for these structural isomers has little influence on energy accommodation and adsorption behavior of gaseous incident particles with similar mass. Moreover, there were no deviations in the measured sticking probabilities when encountering amorphous and crystalline surfaces of cis- and trans-2-butene. The results presented here contribute to our understanding of non-equilibrium sticking and gaseous condensation, enlightening how different factors such as molecular structure, mass, and condensed phase structure influence adsorption dynamics. These results provide valuable insight into heterogeneous adsorption events pertaining to both astrophysical and terrestrial environments.