Sticking coefficient is the term used in surface physics to describe the ratio of the number of adsorbate atoms (or molecules) that do adsorb, or "stick", to a surface to the total number of atoms that impinge upon that surface during the same period of time. Sometimes the symbol S_c is used to denote this coefficient, and its value is between 1.00 (all impinging atoms stick) and 0.00 (none of the atoms stick). The coefficient is a function of surface temperature, surface coverage and structural details as well as the kinetic energy of the impinging particles.