# Can laser beam condense water vapour?

Suppose you pump humidity (water vapour) in an enclosed tank fitted with lasers in all directions, will the water vapour turn to liquid due to collision of photons and $$\text{H}_2\text{O}$$ molecules?... My thought is that when the high speed water vapour molecules collide with photons, they will reduce its velocity thus changing them to liquid water... Am I right?

• What is the color/energy of your photons? Have you computed the allowable change in the momentum of a molecule during a scattering interaction? A search term is “Compton scattering.”
– rob
Nov 29, 2021 at 11:32