Import File Dialog
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Dialog Box - called from: File menu (Startup) or File menu (Graphics)

This dialog is used when importing most types of file format.

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.

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 ATOMS 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.STR will be appended to the structure file.

If the Generate bonds box is checked, the Generate Bonds from Atomic Radii dialog will come up as soon as the file is read in.

Read default display parameters. If this box is checked, the display parameters last saved (Settings menu) will be read for the new data set.

Read temperature factors. This option may not be available for all types of import file. In some file formats, such as ICSD RETRIEVE, the temperature factors are in a separate list from the atomic coordinates. In order to assign the temperature factors to the atoms, the atom labels in these two lists must match exactly. For this reason, "OH" and "OH2" in the atom lists in RETRIEVE files are changed to "O", since the labels in the temperature factor lists use only "O". If you get the message "Temperature factor atom label not identified", you may need to edit the atom labels in the original file so that the two lists agree.

File Extension. The three-letter extension (.xxx) which identifies the file type under Windows (see below for Macintosh) may be specified here - only files of that type will be shown in the Open File dialog. To show all files, enter ".* ".

Atomic Radii. You can choose standard ionic or covalent radii, which will be multiplied by the factor in the edit box. For a ball-and-stick drawing, a factor of 0.5 or less is appropriate. For interpenetrating atoms (space-filling), a factor of greater than 1.0 is usually necessary. All radii can later be multiplied by a given factor in the Atoms-Global command in the Input1 menu. The radii, as well as default colors, are obtained from the selected version of the ELEMENTS file (either ELEMENTS.ION or ELEMENTS.COV) supplied with ATOMS (these files can be modified by the user).

Boundary Option. The boundary option can either be Default Unit Cell, using the default suboption selected in that dialog, or Locate Molecules in Crystal. If the Locate Molecules in Crystal option is used, the Generate bonds box will be considered to be checked, as bonds (or polymers) must be defined.

Source of symmetry (some formats lack this option). If you select Use positions as xyz, in which symmetry operators are given in the form of positions in the general equipoint as in the International Tables, the symmetry option (Input1 Menu) will be Custom Symmetry. After import, you may need to check the Symmetry option to be sure the centric/acentric choice and the Bravais lattice type are correct (some formats include a center of inversion and/or lattice centerings in the operators and some do not). If you select Space group symbol, the Space Group symmetry option will be used. The Hall symbol, the Hermann-Maughin symbol, and then the International Tables number will be used in that order if present. If you select Use positions as xyz and the information on operations is not present, the symmetry option will default to Space group symbol. The H-M space-group symbol, Hall symbol, and space-group number are always read if present.

If symmetry is present in the "xyz" or operation form, this is usually the safest option However, this option does not give information on systematic extinctions or true d-spacings, which may be required for the Slice boundary option. It is usually possible to derive the correct space-group symbols from the operations using the Get Symbol option in the Custom Symmetry dialog.

Atom types (some formats lack this option). ATOMS will try to assign an atomic number to each input atom either from the first one or two characters of the atom label itself, or from a separate atom type label if that is present. In diffraction refinement file formats, this separate atom type label typically identifies the scattering factor, and it it is your choice whether this or the atom label (if either) will identify the element.

Note that in the case of multiple occupancies for a site, ATOMS ignores all but the first atom.

For more information about the specific file types, see one of the following
CCDC FDAT
SHELX-93
CIF
DBWS/LHPM Rietveld
ICSD
ORTEP
XTLVIEW
VIBRAT
PDB
RIETAN
GSAS
AM MINERAL
FULLPROF
Free-Form (.inp)
Ravel ATOMS
WIEN2K

---- Macintosh only ----

You can show all text files, or only those with the specified extension (.xxx) in the File Open dialog - make this choice, which applies to most types of files, in the Preferences dialog in the Settings menu.

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