ISODISTORT

Version History

Harold T. Stokes. Branton J. Campbell, and Dorian M. Hatch
Department of Physics and Astronomy, Brigham Young University, Provo, Utah

Version 5.6.1: August 2013. (1) Fixed the symbols for type-4 magnetic superspace groups.

Version 5.6: July 2013. (1) Revised how strain is applied to a lattice. Compatible with old distortion files.

Version 5.5: June 2013. (1) Made major changes in the appearance and layout of the web pages. (2) Set the 2011 version of IR matrices the default. (3) We redefined how strain modes are normalized. This changes the meaning of strain mode amplitudes from previous versions of isodistort. When you import a distortion file that was created by an earlier version of ISODISTORT, the old normalized modes are automatically used. We also redefined strains in monoclinic and triclinic structures so that the strain modes are orthogonal to each other. (4) Removed esds (estimated standard deviations) from output. As we have added new features to ISODISTORT, these were becoming increasingly cumbersome to calculate. (5) Introduced new nonstandard tags in CIF files to give information about space-group settings. (6) Fixed various bugs that caused ISODISTORT to crash.

Version 5.4.1: (1) Fixed "karms" feature on the distortion page. Sometimes, wrong number of k vectors was listed. Now the feature is called "k-active" and is only displayed if the 2011 version of IR matrices are used. (2) Added list of active arms of the star of k for lists of order parameters (on order parameter direction page) generated by methods 1 and 2. This feature is only displayed if the 2011 version of IR matrices are used.

Version 5.4:
(1) Resolved some problems related to the decomposition of magnetic structures and the output of magnetic symmetry modes, changed the way that magnetic symmetry modes are handled, and changed the way that symmetry mode information is presented in CIFs. If you have old distortion files containing magnetic symmetry modes in supercells with non-orthogonal axes, we recommend that you import and resave them. If you have previously decomposed a magnetic structure where lattice strains were also present, your magnetic mode amplitudes will be slightly off -- redo the decomposition to correct them. If you use CIF-formatted symmetry-mode information (a format in progress), and want to better understand what has changed, feel free to contact us for more information.
(2) Replaced CGI with PHP; may have browser-dependent effects.
(3) Added the capability to create CIF files using nonstandard settings. See the fields at the bottom of the Distortion page.
(4) Added more complete Fullprof output.

Version 5.3:
(1) Superposed IRs with incommensurate k points implemented.
(2) New matrices for many IRs. These new matrices keep the contributions from different k vectors separated in the order parameter.
(3) By popular demand, improved human-readable format for saved distortion files. This fixes the problem with distortion files becoming invalid after short periods of time. Unfortunately, this means that all distortion files generated with earlier versions of ISODISTORT will be invalid. However, we expect that the new distortion files will be backwards compatible with all future versions of ISODISTORT.

Version 5.2:
(1) Amplimode-format output for FullProf

Version 5.1:
(1) Modes details for incommensurate structures. Additional information about individual atoms is given in a new option, "Complete modes details."
(2) Incommensurate magnetic structures for a single IR in search method 2. Implementation of this feature is based on private communication from J. M. Perez-Mato.
(3) Basic space-group setting option for incommensurate structures.

Version 5.0:
(1) Changed name from ISODISPLACE to ISODISTORT, since atomic displacement is only one of four different types of distortions treated.
(2) Magnetic moments and magnetic space groups.
(3) Improved decomposition algorithm in method 4 on the search page, including an optional specification of space-group origin.

Version 4.8:
(1) On the Search page, the user can select what kinds of distortions to consider. Ordering distortions are no longer shown by default, but must be selected here.
(2) User can now save interactive applet images to file. Note that allowing an internet-based applet to save files to your computer requires first accepting a security certificate that is presented when you start the applet. Everything but the new "Save Image" feature should still work if you reject the certificate.

Version 4.7:
(1) The format of the data sent by ISODISPLACE to the interactive java applets (isoDisplaceApplet.jar and isoDiffractApplet.jar) has been changed in order to make it easier for other software packages to utilize the applets.

Version 4.6:
(1) Powder diffraction capabilities added to interactive applet.
(2) Mode decomposition utility now automatically searches for probable superlattice-basis candidates.

Version 4.5:
(1) Fixed the applet so that is runs with the new version of Apple JVM.
(2) Added TOPAS.STR button to export a file for structure refinement using distortion-mode amplitudes.

Version 4.4:
(1) New method for normalization of mode amplitudes
(2) Modes details page
(3) Additional option for search method 3

Version 4.3:
(1) Includes atomic occupancy.

Version 4.2:
(1) ISOCIF utility for creating and modifying CIF files.
(2) Improved choices for monoclinic and triclinic unit cells of distorted structures.

Version 4.0:
(1) Order parameters and slide bars for atomic ordering.
(2) Incommensurate distortions leading to (3+1)-dimensional superspace groups.
(3) Width of applet controlled by user input so that it can fit on low-resolution screens.
(4) Mode decomposition of large structures.
(5) CIF output containing linear transformation between atomic coordinates and mode amplitudes.

Version 3.3:
Interactive visualization of single-crystal x-ray and neutron diffraction patterns