XABS2
4.33 - XABS2 - Empirical Absorption Correction
Synopsis
XABS2 is a program to calculate empirical
absorption corrections from the calculated and observed structure factors.
The original XABS (H. Hope and B. Moezzi, Jul83, Feb84, May85)
obtained 12 coefficients from a linear least-squares fit in
sin**2(theta) to (1/A vs sin**2(theta)), by minimizing weighted
differences between Fo^2 and Fc^2.
XABS2 calculates either 24, 18 or 12 coefficients from a least-squares
fit of (1/A vs sin**2(theta)) to either a cubic, quadratic or linear
equations in sin**2(theta) by minimization of Fo^2 and Fc^2 differences.
You can choose whether to do a linear, quadratic or cubic fit. A cubic fit is
better for Cu Ka radiation with data to 2theta > 90 degrees. A linear fit is
better for Mo Ka or Cu data that has a restricted resolution, such as in
macromolecular crystallography.
The program XABS2 is written by
Sean Parkin et al.
Files read
- name.FCF - written by SHELXL (LIST 4, MERG 0 instructions, based on ISOTROPIC refinement).
- name.INS - for unit cell information only.
Files written
- XABS2.HKL - absorption corrected reflection file
- XABS2.LST - List file giving summary of the applied corrections
- XABS2.CIF - CIF containing relevant information