Three dimensional He scattering on a model surface

He atom beam is scattering on an irregularly stepped model surface. A "window" parallel to the surface has been chosen far from the surface (~10 a.u.) at the detector region. The probability density function (PDF) of He atom is rendered as the time progresses in the above mentioned "window". Atomic units (a.u.) are used.
Animation description:

Firstly the He atoms approach to the Rh(311) surface and the "window" --> PDF increases.
Secondly He atoms pass the "window" and approach to the Rh(311) surface --> PDF deacreses.
Thirdly He atoms scatter on the Rh(311) surface and approach to the detector and the "window" --> PDF increases.
Fourthly the "window" is the same as the detector --> typical diffraction pattern at the detector.

Further details can be found in:

"Resolution and transfer width of thermal energy atomic scattering from solid surfaces, G Varga, Applied Surface Science, 144-145 (1999) p. 64-68 p. 64-68"
or
"Investigation of thermal energy atomic scattering from solid surfaces using 3D time-dependent Schrödinger equation, G. Varga, Surface Science, vol. 441 (1999) 472-478".