In Situ Direct Observation of Adsorption and Desorption on a Single Crystal of 2,4,6-Trinitrophenol (TNP) KovalevAlexander SturmHeinz 2012 For the first time, we report the direct observation of the nanoscale adsorption and desorption of 2,4,6-trinitrophenol (TNP) molecules on the crystal surface during atomic force microscopy scanning. Our results reveal the position instability of TNP molecules at the border of molecular layers under normal ambient conditions. The observed phenomena are of great interest for exploring the origin of hot-spot generation on the surface of energetic materials. On the basis of the explored properties of TNP crystal, a plausible mechanism of hot-spot formation upon weak initiation at the nanoscale is proposed.