Harold T. Stokes. Branton J. Campbell, and Dorian M. Hatch
Department of Physics and Astronomy, Brigham Young University, Provo, Utah
Version 2.6.0, April 2018. ISOCIF now fully supports the atomic rotation vectors generated by ISODISTORT, which are very nicely analogous to magnetic-moment vectors. For a rigid-unit rotation, one can indicated the magnitude and direction of the rotation by assigning a pseudo-vector to the pivot atom (possibly a dummy atom) at the center of the rigid unit. This can be done to match the actual rigid-unit rotation realized in the structure or to indicate a possible but unrealized rotation. ISOCIF does not attempt to actually move the passenger atoms of a rigid-unit to match the pivot-atom rotation vector. The pivot-atom rotation vectors of a structure can represent a pattern of rigid-unit rotations even when no passenger atoms are explicitly given in the CIF.
Version 2.5.1, November 2017. Minor bug fixes.
Version 2.5.0, August 2017. Recent improvements to FINDSYM have propgated to ISOCIF. (1) Fundamental symmetry-detection algorithm and efficiency improvements, particularly for cases involving large numbers of atoms and for cases involving substantial "noise" in the atomic coordinates. (2) Errors encountered at large tolerance values have been resolved. When a large tolerance is requested, that tolerance is now reset to 1/3 the smallest same-atom-type nearest-neighbor distance for each atom type.
Version 2.4.1, January 2017. Minor bug fixes.
Version 2.4.0, November 2016. (1) Now accepts uppercase X,Y,Z symbols in space-group operators from CIF input. (2) Recent improvements to FINDSYM's symmetry-detection routines carry over to ISOCIF. (3) Implemented several user-adjustable tolerances under the "find actual symmetry tab". (4) Because the magCIF format has now been approved by the IUCr, all magnetic CIF read/write routines have been updated to the new standard but can still read magnetic CIF files that use the slightly-different interim standard. The old (pre-May2014) magnetic CIF prototype can no longer be used. (5) Minor bug fixes.
2.3.13, Aug 2016. Preparations for new features.
2.3.12, Oct 2015. Fixed a variety of bugs related to symmetry detection, magnetic symmetry, non-standard settings in CIF output, the ability and efficiency to deal with larger structures, and some minor cosmetic issues.
2.3.8-11, Aug 2014. Various minor bug fixes.
2.3.7, Jun 2014. (1) This version uses the provisional magCIF format for describing commensurate magnetic structures. Commensurate parent and child structures can be imported using either the provisional magCIF format or our older magnetic-CIF format, though the older format will eventually be abandoned. At present, one can use ISOCIF to convert from the old to the new format.
(2) Improved capabilities for dealing with structures with large numbers of atoms.
(3) The ability to read magnetic CIFs in non-standard BNS settings. Upon upload, the structure is transformed to a standard setting, and the transformation matrix is provided to the user.
(4) CIF input must now be uploaded -- the cut/paste options has been eliminated. The separate pre-processed CIF page for reviewng/accepting uploaded CIF content has also been eliminated.
(5) Many incremental developments and bug fixes accumulated during the past year.
2.3.6, May 2013, Introduced new nonstandard tags in CIF files
to give information about space-group settings.
2.3.5, Mar 2013. Fixed bugs that caused the program to crash sometimes.
2.3.4, 22 Jan 2013. Fixed bug. Spurious output produced in CIF file output.
2.3: (1) Displays transformation to current space-group setting (a) when uploaded CIF file is in a non-standard setting and (b) when the "Find actual symmetry" option is selected. (2) Added the capability to create CIF files using nonstandard settings.
2.2: Capability to remove magnetic moments.
2.1: Capability to reduce symmetry to P1.
2.0: Magnetic moments and magnetic space groups.
1.3: Option to change lattice vectors and origin of space group.