February 2010 Archives
For the MX endstation we've characterized the dependence of the direct beam on detector distance and 2-theta. We collected 4 sweeps of the detector from 120mm to 1600mm combined with 2-theta offsets from 0º up to 12º. These are the gnuplot 3D plots of the data.
This set of 3D plots uses gnuplots pm3d settings to generate colorful versions:
Click the images to view larger versions, and hit the "jump" to read the gory details of the polynomial equation used to determine x-beam and y-beam given any value of detector distance (CCD_Z) and 2-theta.
FoXS, a new webapp which uses the Debye formula for calculating theoretical scattering profiles, has been made available on the ModBase website. Give it a try to see how it compares to CRYSOL.
FoXS is a method for computing a theoretical scattering profile of a structure and fitting of experimental profile. FoXS can be used as a basic tool for numerous structural modeling applications with SAXS data:
- Comparison of solution and X-ray structure conformations
- Modeling of different conformation, i.e. model active conformation starting from non-active
- Structural characterization of flexible proteins
- Assembly of multi domain proteins starting from single domain structures
- Assembly of multi protein complexes
- Fold recognition and comparative modeling
- Determination of biologically relevant state from the crystals