X-GEN Manual, Section 5 XSCA (ascii SCALEPACK-style output) File Formats

XSCA is an ascii file written in the style of the SCALEPACK ".sca" file, with the Friedel-mates merged. This file is output from the "makemu" and "scalem" applications of X-GEN. It is always written out along with the file XASCA, which is a SCALEPACK-style output file with the Friedel-mates separated. The format of a reflection line in the XSCA file is:

 h k l I+ sigma(I+)
in format " %3d %3d %3d %7.1f %7.1f"
for all reflections for which the intensity is measured.

The file begins with a three-line header. The first line contains a 1 and the second contains the flag value -985, both in format %5d. The third line contains the unit cell and the spacegroup in the following style:

 a  b  c  alpha  beta  gamma spgrp
in format " %9.3f %9.3f %9.3f %9.3f %9.3f %4s",
where the spacegroup is written in a lower-case, no-subscript form. Thus spacegroup P2(1)2(1)2(1) appears as p212121. This provides an unambiguous rendering for all noncentrosymmetric space groups; whether it works as unambiguously for all centrosymmetric space groups is unclear.

Accordingly the first four lines in a typical file look like

    1
 -985
   111.268   111.268   176.543    90.000    90.000   120.000 p31
   0   2   5   260.6     7.4

Reflections will normally be sorted with L varying fastest, K second-fastest, and H slowest, except in monoclinic spacegroups, where K will vary slowest. In spacegroups where negative indices can appear, the sign flips will be considered as an even faster variation. Thus in a monoclinic spacegroup, (1,2,-5) will follow (1,2,5), and (1,2,6) will follow (1,2,-5).

Usage: $WORK/<idname>.sca
Written from: scalem and makemu.
Edited in: Ordinary text editors
Read in: External packages, too numerous to mention.

Report bugs to Andy Howard at howard@iit.edu or 312-567-5881.