Diffraction Signals
TeraChem can compute elastic and inelastic scattering signals for CAS-type (CASCI and CASSCF) wavefunctions, relevant for X-Ray and electron diffraction experiments. The output will include elastic contributions for x-ray and electron diffraction, as well as the inelastic contribution (which is the same for x-ray and electron diffraction).
Add some description of the basic theory here
Input parameters
| Keyword | Values | Description |
|---|---|---|
| diffraction | yes|no | yes - triggers the computation of the diffraction signal |
| diff_lvalue | -1 | Maximum l for rotational averaging |
| diff_s_start | 0.0 | Scattering vector range is diff_s_start...diff_s_end in increments of diff_delta_s (units of \(bohr^{-1}\)) |
| diff_s_end | 10.0 | |
| diff_delta_s | 0.1 | |
| diff_axis_x | 0.0 | Axis for rotational averaging |
| diff_axis_y | 0.0 | |
| diff_axis_z | 1.0 | |
| diff_rotation_averaging | 0,1,2 | 0 = Uniform averaging of all molecular orientations 1 = \(cos^2(\theta)\) distribution, parallel to specified axis 2 = \(sin^2(\theta)\) distribution, perpendicular to specified axis |