XABS2: A 4-D scale factor originally formulated for approximate treatment of absorption effects [J. Appl. Cryst. (1995). 28, 53-56]. XABS2 has been used in thousands of structures. In spite of the availability nowadays of more rigorous methods, it is still useful. It can be used to treat under correction by face-indexed and multiscan methods. It can also alleviate some effects of anisotropic extinction and scan truncation. XABS2 has long been included the WinGX suite, and a simplified version of the algorithm was included in SHELXL-97 [Acta Cryst. (2008). A64, 112-122]. Nowadays it is most useful as a diagnostic test for whether face-indexed or multiscan absorption correction was adequate. A Windows executable compiled with gfortran is here: xabs2_Win.exe.zip.

RT: An 'R-tensor' that defines an ellipsoid representing 3-D quality of fit. Small ellipsoids equate to a better overall fit, while low eccentricity means a more isotropic fit over reciprocal space. Given a series of refinement strategies for a given structure, the one that leads to the lowest eccentricity is generally the most appropriate. RT is described in Acta Cryst. (2000) A56, 157-162. The concept has been used in other programs, e.g. xd_red-1.0 by R. H. Mathiesen [J. Appl. Cryst. (2001). 34, 785]. RT is used for guiding refinement strategy of problem structures, e.g. to see if one model or another (twinned vs disordered etc.) is better. A Windows executable is here: rt_Win.exe.zip.

ProtRot: Uses quaternions to find the best rotation to superimpose two structures. It was written for protein structure models, and can base comparison on several different sets of atoms (e.g. all atoms, backbone only, Cα only etc.). It uses the algorithm described by S.K. Kearsley [Acta Cryst. (1989). A45, 208-210].


shelxl-launcher: Launches SHELXL and more. This version runs ciffix, RT and ciftab-automator (see below and above).

wghtfix: A bash script that automatically optimizes the SHELXL weighting scheme.

ciffix: A bash script that fixes CIFs from SHELXL-2014 on-the-fly using standard unix tools. Creates CIFs that usually need no further editing.

ciftab-automator: A script that automates the flow of ciftab. It uses expect to bypass the need for keyboard entry.

sadabs-auto and sadabs-auto-run: Scripts that automate SADABS using bash and expect to bypass all keyboard input.

xp-launcher: SHELXL-2014 has a bunch of new commands that XP does not understand. This script tricks XP into civilized behaviour.

xprun: An expect script that launches XP. Also sets preferences that can't be changed with the regular 'sxtl.ini' file. Used with xp-launcher.

xp-proj-enabler: A bash script that fixes 'proj' rotation in XP. Called by xp-launcher.

xpdraw: Combines xpfix and plt2ps so that XP '.plt' files are converted to '.ps'. Also makes subtle changes to colours. Invokes plt2ps (see below).

plt2ps: An expect script that converts '.plt' files created by George Sheldrick's XP program to PostScript format. Called by xpdraw.

isot: A bash script that converts all anisotropic temperature factors in a shelxl file to isotropic.

sfrmhead: A bash script that extracts the header from a Bruker-AXS *.sfrm X-ray diffraction image file..

awkhkl: An awk one-liner that extracts experimental reflection data from a shelxl '.fcf' file and writes a '.hkl' file.

save: Makes a tarball of all files needed to continue refinement on a different computer. Invokes secure copy to move the *.tbz.


xpfix: Superceded by xpdraw, supercedes ps2. Makes subtle changes to colours in XP PostScript files.

ps2: Superceded by xpfix. Darkens the greys and converts PostScript files from XP to '.pdf'.


How to run the Shelxtl XP molecule editor on a Mac (OSX 10.7 - 10.12.6).

How to run the Shelxtl XP molecule editor on a Mac (up to OSX 10.6.8).