Comment on “Femtosecond near-infrared laser desorption of multilayer benzene on Pt(111): spatial origin of hyperthermal desorption” [Chem. Phys. Lett. 314 (1999) 389–395]

A number of photodesorption studies have recently been carried out with multilayer films. As the flight time profiles are often poorly reproduced by one or two Maxwellian distributions, a sum of modified Maxwellians is used. The fit parameters involved can be underdetermined or result in physically unreasonable values. It is therefore suggested to avoid temperatures for describing highly non-thermal velocity distributions, and instead to determine the time-dependent desorption flux from the multilayer films.