| 1 | <html> |
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| 2 | <head> |
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| 3 | <META NAME="Author" CONTENT="Brian H. Toby"> |
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| 4 | <title>EXPGUI Tutorial #5</title> |
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| 5 | </head> |
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| 6 | <BODY BGCOLOR="#FFFFFF"> |
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| 7 | |
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| 8 | <A HREF=http://www.ncnr.nist.gov> |
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| 9 | <IMG SRC="http://www.ncnr.nist.gov/images/ncnrtrans.gif" |
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| 10 | alt="Link to NIST Center for Neutron Research home page" |
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| 11 | ALIGN=RIGHT></A> |
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| 12 | <A HREF=http://www.nist.gov> |
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| 13 | <IMG SRC="http://www.ncnr.nist.gov/images/webidblue_2lineright.gif" |
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| 14 | alt="Link to National Institute of Standards & Technology home page" |
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| 15 | ALIGN=LEFT></A> |
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| 16 | <CENTER> |
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| 17 | <A Href="http://www.ncnr.nist.gov/programs/crystallography/software/tclpkgs.html"> |
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| 18 | <IMG SRC="tcltklogo100.gif" |
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| 19 | alt="Link to Tcl/Tk information"> |
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| 20 | </CENTER></A> |
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| 21 | <hr> |
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| 22 | |
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| 23 | <CENTER> |
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| 24 | <H1>EXPGUI Tutorial: Garnet (part 5)</H1> |
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| 25 | </CENTER> |
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| 26 | <H1> |
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| 27 | 5. Plot data using POWPLOT or LIVEPLOT |
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| 28 | </H1> |
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| 29 | At this point in the GSAS tutorial in the manual, |
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| 30 | program POWPLOT is used to plot the diffraction data. This |
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| 31 | is done by pressing POWPLOT button in the button bar, or |
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| 32 | by pressing the POWPLOT menu item in either the Powder menu |
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| 33 | or the Graphs menu. The input supplied to POWPLOT and the |
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| 34 | results are the same as what is shown in the menu, so this will |
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| 35 | not be shown. |
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| 36 | <P> |
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| 37 | EXPGUI does offer another way to display diffraction data, LIVEPLOT. |
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| 38 | Similar to the way POWPREF was run in the previous step, |
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| 39 | LIVEPLOT can be started by pressing LIVEPLOT button in the button bar, |
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| 40 | or by pressing the LIVEPLOT menu item in the Graphs menu. |
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| 41 | <P> |
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| 42 | <a name="diff"> |
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| 43 | <img src="lp1.gif"></a> |
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| 44 | <BR clear=left> |
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| 45 | Since two cycles of refinement have been run, |
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| 46 | LIVEPLOT generates a plot similar to the one above, showing the |
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| 47 | observed data (black X's), simulated (computed) data (red line), the fitted |
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| 48 | background (green line) and the difference between the observed and computed |
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| 49 | data (lower black line), |
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| 50 | <BR clear=left><P> |
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| 51 | <img src="lp2.gif"> |
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| 52 | <BR clear=left> |
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| 53 | Note that the region shown in the plot |
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| 54 | can be changed by clicking with the left |
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| 55 | mouse button to outline a region, as shown above. |
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| 56 | When the left mouse button is pressed a second time, the graph is "zoomed in," |
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| 57 | as is shown below. |
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| 58 | To "zoom out" to the previous region, press the right mouse button. |
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| 59 | <BR clear=left><P> |
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| 60 | <img src="lp3.gif"> |
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| 61 | <BR clear=left><P> |
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| 62 | <img src="lp4.gif"> |
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| 63 | <BR clear=left> |
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| 64 | Reflection positions can be marked, using the File/Tickmarks menu. |
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| 65 | Likewise, reflection indices can be displayed by pressing the "h" (or "H") key in the |
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| 66 | position of the reflection to be labeled. |
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| 67 | The size and time before |
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| 68 | the reflection labels are removed is determined by values in the Options/HKL labeling menu. |
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| 69 | <BR clear=left><P> |
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| 70 | There are many other options available in LIVEPLOT in the Options menu. The |
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| 71 | Appearance and location of the tickmarks can be set, |
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| 72 | for example, using the "Options/Configure Tickmarks/Auto locate option |
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| 73 | causes the tickmarks to be shown as |
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| 74 | <A HREF="garnet6.html#ticks">small lines under each reflection.</A> |
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| 75 | The symbol and symbol size |
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| 76 | used for observed data can be selected. |
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| 77 | The X and Y units can be changed to Q or d-space values. Background |
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| 78 | can be subtracted. The legend can be removed from the plot. |
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| 79 | |
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| 80 | <BR clear=left><HR> |
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| 81 | Previous step: <A HREF="garnet4.html"> |
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| 82 | Run POWPREF and GENLES</A> |
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| 83 | <BR> |
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| 84 | Next step: <A HREF="garnet6.html"> |
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| 85 | Additional Least-Squares Refinement</A> |
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| 86 | |
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| 87 | |
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| 88 | <BR clear=left> |
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| 89 | <HR><p><a href="http://www.ncnr.nist.gov/staff/toby/">Brian Toby</a> (<a href="mailto:brian.toby@nist.gov">Brian.Toby@NIST.GOV</a>) |
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| 90 | <BR clear=left> |
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| 91 | $Revision: 191 $ $Date: 2009-12-04 23:01:55 +0000 (Fri, 04 Dec 2009) $ |
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| 92 | </body> |
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| 93 | </html> |
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