CrystalDiffract POWDER DIFFRACTION SOFTWARE FOR MacOS
CrystalDiffract is a program to generate, display and manipulate x-ray and neutron powder diffraction patterns. CrystalDiffract is designed as a stand-alone program - but you will require the CrystalMaker program if you wish to generate crystals and diffraction patterns which are not included with the standard package. (See the help section "Ordering CrystalMaker" for more details).
CrystalDiffract requires around 2 MB of RAM free — though the exact amount depends on the number, and size of your graphics windows. You must be running MacOS version 7.0, or later. Your machine must have an mc68020 processor, or higher — or a PowerPC chip.
CrystalDiffract is available in different versions, optimized for different processors. Please ensure that you have the correct version:-
• 68K Macs (i.e., non-PowerPC): 020 version or 020FPU version (for math-coprocessors/FPU)
• PowerPC Macs: PPC version
We also supply a "FAT" binary version, which will run optimally on both 020 Mac's and PowerPC Macs's - check the name of the program when you download it! If you have the FAT version, and your machine is a 68K FPU machine, you might want to download the FPU version of CrystalDiffract from our web site (the FPU version is approximately 3 times faster than the 020 version).
AppleGuide Online Help CrystalDiffract has a highly-comprehensive online help system, featuring full AppleGuide support. To use this, you must be running System 7.5, or later, and have the AppleGuide system software installed.
Getting Started with CrystalDiffract
Displaying A Diffraction Pattern
To generate and display a diffraction pattern, you must first open a Crystal file using CrystalDiffract. Either:
• In the Finder, drag a Crystal file icon onto the CrystalDiffract application icon
or/
• Launch CrystalDiffract, and select the Open command from the File menu, then choose a Crystal file to be opened.
If CrystalDiffract is able to read the Crystal file correctly, a graphics window will open, a diffraction pattern will be generated (this might take some time for non-PowerPC machines), and the results will be plotted.
Note that CrystalDiffract allows you to open multiple windows.
Toolbar
You can use the four tools (info, scroll, magnify, distance) on the left-hand side of the toolbar, to manipulate your diffraction pattern. There are also six scaling tools, including an auto-scale tool. At the right-hand-side of the toolbar are three "shortcut" tools: clone window; synchronize windows; help.
You can move the toolbar around your screen by clicking its drag area (on the left-hand side). You can also change the shape of the toolbar by clicking the tiny "arrow" icon on the right-hand side. You can either have a "tall" toolbar, with the text area beneath the buttons (this is the default setup), or you can have a "wide" toolbar, with the text area to the right of the buttons.
Editing Crystal Data
Select the "Crystal…" command from the "Edit" menu. A dialog box appears letting you edit:-
• site occupancies for each atom in the asymmetric unit (click on a list row to reveal the editor fields). You can have up to 3 elements on each site, but the total occupancy cannot exceed 1.0. For example, you could model the diffraction from a disordered CuZn solid solution at high-temperatures: edit each site so that it contains Cu 0.5 and Zn 0.5 (instead of either Cu 1.0 or Zn 1.0).
When you've finished editing, click the OK button to replot the diffraction pattern, or hold down the OPTION key on your keyboard, and click OK to replot in a new window.
Dual-Wavelength Radiation
CrystalDiffract is set up to use monochromatic (single-wavelength) radiation. If you wish to model the behaviour of a traditional x-ray tube, with Kalpha-1 and Kalpha-2 x-rays, select the "Wavelenth…" command from the "Diffract" menu, and uncheck the "monochromatic" checkbox. You can now enter two wavelength values. We've provided some pre-set radiation wavelengths, corresponding to Mo, Cu, Co, Fe target materials - click the relevant button.
The ASF.dat file
The amplitude of x-ray radiation scattered by a single atom is defined by the atomic scattering factor (ASF). Its angular dependence is summarized in a 9-coefficient polynomial equation. The coefficients for the more common elements are located in the "ASF.dat" file - and you can add more element data if you wish.
CrystalDiffract attempts to open "ASF.dat" when it is first launched. If you do not supply an ASF.dat file, the program will use default coefficients (equating all atoms to Silicon).
Values for the ASF coefficients may be found in the International Tables for Crystallography, or in: Doyle & Turner (1968) Acta Crystallographica A24:390–397.
More Information about CrystalDiffract
• If you have MacOS 7.5, or later, and have AppleGuide installed, you can use CrystalDiffract's fully-comprehensive online help system. Select the "CrystalDiffract Guide" command from the "Help" menu (the "?" menu on pre-MacOS8 machines).
Problems, Suggestions, Queries?
Contact the program's author, David Palmer, by e-mail at: D.C.Palmer@crystalmaker.co.uk. I wrote this program to help with research and teaching my students. I hope you find it useful too.
About…
CrystalMaker-2
Interactive Crystallography for Macintosh
CrystalMaker-2 is a program for displaying all kinds of crystal structures in stunning, photorealistic colour.
• Build Crystals Fast! Defining a crystal is very simple and requires the minimum of information. Ball-and-stick, space-filling, wire-frame, polyhedral, stick and cloud "dot surface" models are immediately available, and can be extensively customized.
• Real-Time Rotation - just click & drag with the mouse!
• Photo-realistic Displays: full rendering, depth-cueing perspective, etc.
• Flexible Plot Modes: Additional plot modes for diagrams in journals or lecture handouts - variety of polyhedral shaded fill-patterns and atom & bond styles.
• Interactive bond searching - investigate local environments
• Toolbars - lasso tool; info tool; rotate tool; scroll tool; measure bond distances & angles on screen; zap atoms tool
• Export text and graphics files
• Imports ICSD, CIF, CSSR, CCL, STRUPLO, MacMolecule and CrystalMaker text files
• High-quality printing
• Record QuickTime video, plus save self-contained fully-rotating crystals as QuickTime VR object movies!
• User-friendly - exclusively Macintosh.
• Crystal structures library - over 300 structures, including 200 minerals (including most of those listed in the student edition of Deer Howie & Zussman). Ideal for teaching and research.
• High-quality printed manual (220 pages).
CrystalMaker is a low-cost, high-value software package. We give very generous academic discounts, and our 10- and 20-user group licences are amazing value.
CrystalMaker is marketed by:-
Cambridge University Technical Services Ltd.,
20 Trumpington Street. Cambridge, CB2 1QA, UK
Tel.: +44 (1223) 334755 • Fax.: +44 (1223) 332797
E-mail: sjm21@cus.cam.ac.uk
For technical details, send e-mail to: info@CrystalMaker.co.uk
ATTENTION JAPANESE USERS! You can now order CrystalMaker in Japan, via:
NetScience Division
DigitalWare Co., Ltd.
Shinjuku I-Land Tower 31F
6-5-1 Nishishinjuku, Shinjuku-ku,
Tokyo, 163-1366 Japan
tel : +81-3-5381-7580
fax : +81-3-5381-7321
e-mail address : info@dware.co.jp
web address : http://www.dware.co.jp/netscience
Check out our web site at:-
http://www.crystalmaker.co.uk/
You can download a demo version of CrystalMaker from this site! We also include pointers to other download sites, in the U.K. and U.S.A., for alternative ftp file transfer.
