ICDD PDF-4+ 2012 Instructions

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match your experiment (i.e. Type = Ka1 or Ka1+2 and Anode = Co, Cu or Mo as appropriate). 4. If you wish to export the selected PDF card(s) as simulated profile(s), the easiest and quickest way to broaden the simulated profile peaks to more closely match yours is to click on the Simulated Profile tab and change the ‘Profile’ setting from Pseudo-‐ Voigt to Crystallite Size and change the Mean Crystallite Diameter from e.g. 25 to 250 – play around and see. This does not imply anything about the crystallite size in your specimen! Click OK. 5. If you wish instead to export the selected PDF card(s) as stick traces (i.e. peaks with no width), click Plots and Add Stick Trace. Enter the correct PDF Card number, and click Open. Click OK to accept the default ‘Fixed Slit Intensity’ type. Finally, click Plots, Delete, and select the entry for the full simulate profile – this will be the one with the full stoichiometry, PDF card number AND comments about Experimental Intensity). Click OK and then Delete. 6. Repeat if and as appropriate for other PDF card(s). 7. Once you are satisfied, click File, Save. Change ‘Files of Type:’ to JPEG and give a file name. This JPEG will be an image file that you can then view or import in to Word, Powerpoint etc. as a picture file.
Common problems ‘I have found a card with peaks in similar positions, but shifted to higher/lower angle’ This can have three possible causes: 1. Sample height displacement – even a small error in the height of the sample will have an impact on peak position. This error may appear fairly linear with diffracted angle. This is a very common, but largely avoidable, problem. Run the sample again, with more attention to correct sample height. 2. Wrong wavelength selected – either when importing the data (copper is the default), or in Search/Match (other people may have changed this). If the peak shift is dramatically different, this may be the cause. 3. Change in chemistry – if you can replace an element in the crystal structure with another, this is likely to cause changes in the shape and size of the unit cell. You may get the same pattern of peaks, but shifted to higher or lower angles. In this case, the shift is likely to be small at low angles, and significantly larger at higher angles. ‘The intensities on the PDF card are odd – they’re all multiples of 10, or 20!’ This would indeed be quite odd for a real sample! Most likely the data have been collected using an old photographic film technique; check the card text entry for the method used – perhaps it says a Guinier diffractometer was used, or that intensities were obtained via ‘visual’ or ‘densitometer’ methods. Such techniques are extremely accurate; however, the ability of the researcher to accurately interpret the data is more limited! Use such cards with caution.
Page 1 and 2: ICDD PDF-‐4+ and SIeve+ Softwar
Page 3 and 4: Setting up your data The first thin
Page 5 and 6: Searching the Database The database
Page 7 and 8: Starting SIeve+ and loading your da
Page 9: your sample. The software will then
Page 13 and 14: It can immediately be seen that the
Page 15 and 16: Example 2: Nb,Cu-‐doped Titaniu
Page 17 and 18: slightly different composition (whi
Page 19 and 20: By also accepting the Si card, SIev
Page 21 and 22: Next, I select the elements of inte
Page 23 and 24: Further Reading The ICDD software h
Page 25 and 26: Appendix 2: Quality Marks The edito

ICDD PDF-4+ 2012 Instructions

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