Dialog Box: Import File [File menu (Graphics Window) or File menu (Startup Window)]
If there is a data set in memory which has been modified, you are asked if you want to save the changes - see the Close command. Also, you have the option of importing the new data as an epitaxial crystal. If you select the epitaxial option, you will be routed to the Epitaxial Relations dialog after the file has been read.
SHAPE obtains only the title, the unit-cell parameters, the crystal class or point group and the space group from most import files - however the forms can also be obtained from Free-Form (.inp) Files. The space group symmetry is only used in the Donnay-Harker Morphology option (Input1 menu).
If there is more than one data set or phase in the file, the Data Sets...in Import File dialog will present you with a list. The name of the SHAPE data file will be taken from the name of the file, and the title (Title/Axes dialog in the Input1 Menu) will be taken from the data set or phase. The extension .SHP will be appended to the structure file, replacing the original extension.
Read default display parameters . If this box is checked, the display parameters last saved (Settings menu) will be read for the new data set.
File Extension . The three-letter extension (.xxx) which identifies the file type may be specified here - only files of that type will be shown in the Open File dialog. To show all files, enter ".* ".
Source of symmetry (some formats lack this option). Space-group symmetry in the import files is given in one or both of two basic ways; as a space-group symbol or number, or in the form of matrices.
Symbol. If you select this option, the Hall symbol, the Hermann-Maughin symbol, and then the International Tables number will be used in that order if present (CIF files are the only type which is likely to contain the Hall symbol).
Use positions as xyz . If matrices are given, they are most often in the "xyz" form, in which symmetry operators are given as positions in the general equipoint as in the International Tables for X-ray Crystallography. This option also applies to cases in which the matrices are given in all-numerical format, such as ORTEP and RIETAN files - currently in all such cases there is no choice of symmetry format. SHAPE will try to identify the space-group from the matrices - for this to be successful, the space group must be in one of the standard settings used in SgInfo. The allowed settings are listed in the file HALL.DAT. SHAPE does not store the matrices, only the valid space-group symbols.
If the information for the symmetry option selected is not present, the other option will usually be tried. However, if identification of space-group symmetry fails, it may sometimes be necessary to re-import the file, with the other option selected. Whether the symbol or matrices are used to obtain the space group, it must be in one of the standard settings listed in the HALL.DAT file. If the setting in the file is not one of the standard ones, it may be necessary to select the space group manually in the Donnay-Harker Morphology dialog (Input1 dialog). The choice of origin in the space group is not used by SHAPE; however, the orientation may be important as SHAPE only uses certain orientations, in particular the unique axis must be b for monoclinic crystals and c in other cases (except for trigonal rhombohedral). Also, some trigonal, tetragonal and hexagonal point groups may have alternate orientations of the symmetry elements with respect to the crystallographic a -axes - see Symmetry. It may be necessary to change the point group or crystal class to agree with the space-group setting.
Currently the following types of files are supported:
CCDC FDAT files from the Cambridge Crystallographic Data Centre.
SHELX .INS files from the program system of Prof. G. Sheldrick.
CIF - Crystallographic Information Files.
DBWS/LHPM Rietveld input files.
ICSD Inorganic Crystal Structure Database files. Three types of ICSD file are supported, classified according to source: 1) Files from the current CD-ROM database, accessed by the program RETRIEVE. The RETRIEVE files must be written from the DATA window using the PRINT option, not as export files (if there is sufficient demand, export files may be supported). That is, the file should be a copy of what is shown on the screen in the RETRIEVE program. 2) Files from the Canadian Scientific Numeric Database System (CAN/SND). This service may no longer be available. The files are referred to as CRYSTIN. 3) Files from the Netherlands CAOS information system. These files are also referred to as CRYSTIN.
ORTEP Original or ORTEP II atom information.
XTLVIEW Drawing program.
VIBRAT (.VBR) Graphic data files from VIBRAT or VIBRATZ (Shape Software).
ATOMS Structure drawing program (Shape Software).
RIETAN Rietveld program files.
GSAS Data files (.EXP) files from the Los Alamos Lab system.
AM MINERAL Data files from the American Mineralogist structure data base. This is currently available on the Internet at www.geo.arizona.edu/xtal-cgi.test.
FULLPROF . All-purpose refinement program.
RAVEL ATOMS This program is not the same as ATOMS by Shape Software, but is for EXAFS Analysis.
WIEN2K The program package WIEN2k performs electronic structure calculations of solids using density functional theory (DFT). CRYSCON will read the .struct input files, but will only recognize file extensions with three characters, so it may be necessary to rename the files, search manually in the File Open dialog (enter *.struct) or use the "all files" option.
IZA (zeolites). Files from the International Zeolite Association database.
FREE-FORM (.INP). Files of this type are read and written by ATOMS and CRYSCON (Shape Software). Atomic-coordinate information is ignored. All information needed for a SHAPE calculation can be entered with these files, and they should be easy to write with other software.