# MARE

## Function

MARE is an widget based graphical interface to calculate:

- Spaghetti plots (lambda versis Psi for multiple crystal reflection)

- The Umweganregung peak location plot (the diffracted wavelength lambda vs. Psi) for a given primary reflection,i.e., an horizontal cut of the spaghetti plot.

- The Glitches spectrum (the negative intensity for versus the wavelength) or a vertical cut of the spaghetti plot.

## Documentation

- application doc

- input parameters

## Technical aspects

- Limitations:

- Any crystal structures is allowed, but tests have been done only on cubic structures

- Intensity model very simple:

- The formula is not valid for perfect crystals, only for powders.

- The total intensity must be the sum of the primary reflection plus the intensity of the so-called operative reflections plus the contribution of the cooperative ones.

- Anomalous scattering factors are not considered.

- The lorentz and polarization factor are not correctly used

Reference:

B.H. Cole et al, "Simultaneous Diffraction: Indexing Umweganregung Peaks in Simple Cases", Acta Cryst. (1962), 15, 138-144