Adsorption in Geant4?

Two questions.

Is there physics in G4 that allows for physisorption (or chemisorption)?

Right now I have made a detector construction of 2 layers, one of a metal and another very thin layer contacting with hydrogen at the concentration partly dictated by a Langmuir isotherm. Any opinions on this approach?

Hello,

there are at least neutron capture, optical photon absorption. You may add your own absorption process.

VI

My understanding is that absorption can be simulated just as a mix of materials, but there is no clear way in my mind to simulate adsorption (physisorption or chemisorption).

Best i came up with was to apply the appropriate Langmuir isotherm multiplied by the percentage of bonding sites (i.e. the carbon on the surface of steel) with <1um layer thickness.

I was hoping maybe there was a way Geant4 could automatically generate an object with a material adsorbed to the surface and/or simulate adsorption over time. It was a long shot in my mind but thought I’d ask.