Changeset 3481


Ignore:
Timestamp:
Jul 18, 2018 2:51:46 PM (5 years ago)
Author:
vondreele
Message:
 
File:
1 edited

Legend:

Unmodified
Added
Removed

  • Tutorials/SimpleMagnetic/SimpleMagnetic.htm

    r3480 r3481  
    2323  <o:Author>Von Dreele</o:Author>
    2424  <o:LastAuthor>vondreele</o:LastAuthor>
    25   <o:Revision>17</o:Revision>
    26   <o:TotalTime>6201</o:TotalTime>
     25  <o:Revision>18</o:Revision>
     26  <o:TotalTime>6202</o:TotalTime>
    2727  <o:Created>2017-08-09T17:16:00Z</o:Created>
    28   <o:LastSaved>2018-07-18T19:38:00Z</o:LastSaved>
     28  <o:LastSaved>2018-07-18T19:51:00Z</o:LastSaved>
    2929  <o:Pages>1</o:Pages>
    3030  <o:Words>5837</o:Words>
    … …  
    17161716src="SimpleMagnetic_files/image001.png" v:shapes="Picture_x0020_1"><![endif]></span></p>
    17171717
    1718 <p class=MsoNormal>To have this result, one assumes that the neutron beam is
    1719 not polarized, the sample has no texture and there is only elastic scattering.
    1720 The first term is the ordinary nuclear structure factor found for all
    1721 crystalline materials and the second is the magnetic scattering. Note that the
    1722 result is a sum of squares implying that the nuclear and magnetic scattering
    1723 intensities are summed to give the total that is measured in a magnetic powder
    1724 diffraction experiment. This allows us to model the structure as two separate
    1725 crystalline phases; one consists of the chemical arrangement of all the atoms
    1726 in the crystal structure described with a conventional unit cell and space
    1727 group, and the other contains only the magnetic atoms in a perhaps different
    1728 unit cell with a magnetic space group to describe the atom and magnetic moment
     1718<p class=MsoNormal>To have this result, one assumes that the neutron beam is not
     1719polarized, the sample has no texture and there is only elastic scattering. The
     1720first term is the ordinary nuclear structure factor found for all crystalline
     1721materials and the second is the magnetic scattering. Note that the result is a
     1722sum of squares implying that the nuclear and magnetic scattering intensities
     1723are summed to give the total that is measured in a magnetic powder diffraction
     1724experiment. This allows us to model the structure as two separate crystalline
     1725phases; one consists of the chemical arrangement of all the atoms in the
     1726crystal structure described with a conventional unit cell and space group, and
     1727the other contains only the magnetic atoms in a perhaps different unit cell
     1728with a magnetic space group to describe the atom and magnetic moment
    17291729arrangement. Needless to say both phases must describe the same atomic
    17301730arrangement for the magnetic ions; these will be linked as needed by
    … …  
    18701870 <v:imagedata src="SimpleMagnetic_files/image005.png" o:title=""/>
    18711871</v:shape><![endif]--><![if !vml]><img border=0 width=426 height=289
    1872 src="SimpleMagnetic_files/image003.png" v:shapes="Picture_x0020_3"><![endif]></span></h2>
     1872src="SimpleMagnetic_files/image078.png" v:shapes="Picture_x0020_3"><![endif]></span></h2>
    18731873
    18741874<p class=MsoNormal><span class=GramE>and</span> the plot window will show the
    … …  
    18801880 <v:imagedata src="SimpleMagnetic_files/image007.png" o:title=""/>
    18811881</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=535
    1882 src="SimpleMagnetic_files/image004.png" v:shapes="Picture_x0020_4"><![endif]></span></p>
     1882src="SimpleMagnetic_files/image080.png" v:shapes="Picture_x0020_4"><![endif]></span></p>
    18831883
    18841884<h3>Step 2: Select Limits </h3>
    … …  
    19211921 <v:imagedata src="SimpleMagnetic_files/image009.png" o:title=""/>
    19221922</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=535
    1923 src="SimpleMagnetic_files/image006.png" v:shapes="Picture_x0020_5"><![endif]></span></p>
     1923src="SimpleMagnetic_files/image081.png" v:shapes="Picture_x0020_5"><![endif]></span></p>
    19241924
    19251925<h3>Step 3: Read in the chemical structure for LaMnO<sub>3</sub></h3>
    … …  
    20082008 <v:imagedata src="SimpleMagnetic_files/image012.png" o:title=""/>
    20092009</v:shape><![endif]--><![if !vml]><img border=0 width=539 height=278
    2010 src="SimpleMagnetic_files/image008.png" v:shapes="Picture_x0020_7"><![endif]></span></p>
     2010src="SimpleMagnetic_files/image082.png" v:shapes="Picture_x0020_7"><![endif]></span></p>
    20112011
    20122012<h3>Step 4. Check powder pattern indexing</h3>
    … …  
    20292029 <v:imagedata src="SimpleMagnetic_files/image014.png" o:title=""/>
    20302030</v:shape><![endif]--><![if !vml]><img border=0 width=543 height=195
    2031 src="SimpleMagnetic_files/image010.png" v:shapes="Picture_x0020_8"><![endif]></span></p>
     2031src="SimpleMagnetic_files/image083.png" v:shapes="Picture_x0020_8"><![endif]></span></p>
    20322032
    20332033<p class=MsoListParagraphCxSpMiddle style='margin-left:.25in;mso-add-space:
    … …  
    20632063 <v:imagedata src="SimpleMagnetic_files/image016.png" o:title=""/>
    20642064</v:shape><![endif]--><![if !vml]><img border=0 width=548 height=197
    2065 src="SimpleMagnetic_files/image013.png" v:shapes="Picture_x0020_9"><![endif]></span><br>
     2065src="SimpleMagnetic_files/image084.png" v:shapes="Picture_x0020_9"><![endif]></span><br>
    20662066showing the lattice constants for LaMnO3 you had obtained from the <span
    20672067class=SpellE>cif</span> file. Note that the space group is set to that of the <span
    … …  
    20832083 <v:imagedata src="SimpleMagnetic_files/image018.png" o:title=""/>
    20842084</v:shape><![endif]--><![if !vml]><img border=0 width=552 height=473
    2085 src="SimpleMagnetic_files/image015.png" v:shapes="Picture_x0020_10"><![endif]></span></p>
     2085src="SimpleMagnetic_files/image085.png" v:shapes="Picture_x0020_10"><![endif]></span></p>
    20862086
    20872087<p class=MsoListParagraphCxSpMiddle style='margin-left:.25in;mso-add-space:
    … …  
    21012101 <v:imagedata src="SimpleMagnetic_files/image020.png" o:title=""/>
    21022102</v:shape><![endif]--><![if !vml]><img border=0 width=548 height=470
    2103 src="SimpleMagnetic_files/image017.png" v:shapes="Picture_x0020_11"><![endif]></span></p>
     2103src="SimpleMagnetic_files/image086.png" v:shapes="Picture_x0020_11"><![endif]></span></p>
    21042104
    21052105<p class=MsoListParagraphCxSpMiddle style='margin-left:.25in;mso-add-space:
    … …  
    21212121 <v:imagedata src="SimpleMagnetic_files/image022.png" o:title=""/>
    21222122</v:shape><![endif]--><![if !vml]><img border=0 width=544 height=466
    2123 src="SimpleMagnetic_files/image019.png" v:shapes="Picture_x0020_12"><![endif]></span><br>
     2123src="SimpleMagnetic_files/image087.png" v:shapes="Picture_x0020_12"><![endif]></span><br>
    21242124Notice that the 1<sup>st</sup> peak (as well as the contaminant) is no longer
    21252125indexed; this is likely to be a magnetic only peak as expected from an
    … …  
    21542154 <v:imagedata src="SimpleMagnetic_files/image024.png" o:title=""/>
    21552155</v:shape><![endif]--><![if !vml]><img border=0 width=540 height=195
    2156 src="SimpleMagnetic_files/image021.png" v:shapes="Picture_x0020_13"><![endif]></span></p>
     2156src="SimpleMagnetic_files/image088.png" v:shapes="Picture_x0020_13"><![endif]></span></p>
    21572157
    21582158<p class=MsoListParagraphCxSpMiddle style='margin-left:.25in;mso-add-space:
    … …  
    21982198 <v:imagedata src="SimpleMagnetic_files/image026.png" o:title=""/>
    21992199</v:shape><![endif]--><![if !vml]><img border=0 width=256 height=214
    2200 src="SimpleMagnetic_files/image023.png" v:shapes="Picture_x0020_14"><![endif]></span></p>
     2200src="SimpleMagnetic_files/image089.png" v:shapes="Picture_x0020_14"><![endif]></span></p>
    22012201
    22022202<p class=MsoListParagraphCxSpMiddle style='margin-left:.25in;mso-add-space:
    … …  
    22102210 <v:imagedata src="SimpleMagnetic_files/image028.png" o:title=""/>
    22112211</v:shape><![endif]--><![if !vml]><img border=0 width=256 height=214
    2212 src="SimpleMagnetic_files/image025.png" v:shapes="Picture_x0020_15"><![endif]></span></p>
     2212src="SimpleMagnetic_files/image090.png" v:shapes="Picture_x0020_15"><![endif]></span></p>
    22132213
    22142214<p class=MsoListParagraphCxSpLast style='margin-left:.25in;mso-add-space:auto'>It
    … …  
    22252225<h3>Step 5. Make the magnetic phase</h3>
    22262226
    2227 <p class=MsoNormal>In the previous step we did not have to resort to any
    2228 doubling of a cell axis to explain the suite of magnetic reflections, so the
    2229 propagation vector is zero (in case anyone asks!). To make the magnetic cell
    2230 from the chemical cell we will use the transform tool that is in GSAS-II in the
    2231 General tab for the chemical structure. That tab is</p>
     2227<p class=MsoNormal>In the previous step we did not have to resort to any doubling
     2228of a cell axis to explain the suite of magnetic reflections, so the propagation
     2229vector is zero (in case anyone asks!). To make the magnetic cell from the
     2230chemical cell we will use the transform tool that is in GSAS-II in the General
     2231tab for the chemical structure. That tab is</p>
    22322232
    22332233<p class=MsoNormal><span style='mso-no-proof:yes'><!--[if gte vml 1]><v:shape
    … …  
    22362236 <v:imagedata src="SimpleMagnetic_files/image030.png" o:title=""/>
    22372237</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=307
    2238 src="SimpleMagnetic_files/image027.png" v:shapes="Picture_x0020_16"><![endif]></span></p>
     2238src="SimpleMagnetic_files/image091.png" v:shapes="Picture_x0020_16"><![endif]></span></p>
    22392239
    22402240<p class=MsoNormal>Under the <b style='mso-bidi-font-weight:normal'><span
    … …  
    22542254
    22552255<p class=MsoNormal>The order of operations for the transformation is given at
    2256 the top of the window; the U vector permits applying an origin shift to the
    2257 atom coordinates before the transformation and the V vector is for an origin
    2258 shift after the transformation. The lattice parameters are transformed by
    2259 changing the metric tensor via</p>
     2256the top of the window; the U vector permits applying an origin shift to the atom
     2257coordinates before the transformation and the V vector is for an origin shift
     2258after the transformation. The lattice parameters are transformed by changing
     2259the metric tensor via</p>
    22602260
    22612261<p class=MsoNormal><o:p>&nbsp;</o:p></p>
    … …  
    22842284
    22852285<p class=MsoNormal>The dialog box gives an extensive list of commonly used
    2286 transformations for e.g. swapping axes. In this case we are not transforming
    2287 the unit cell so the matrix is just the unit matrix (ones on diagonal) and we
    2288 are not shifting the origin so U &amp; V are zeros. We do want the new phase to
    2289 be magnetic so press the <b style='mso-bidi-font-weight:normal'><span
     2286transformations for e.g. swapping axes. In this case we are not transforming the
     2287unit cell so the matrix is just the unit matrix (ones on diagonal) and we are
     2288not shifting the origin so U &amp; V are zeros. We do want the new phase to be
     2289magnetic so press the <b style='mso-bidi-font-weight:normal'><span
    22902290style='font-family:"Calibri",sans-serif;mso-ascii-theme-font:minor-latin;
    22912291mso-hansi-theme-font:minor-latin;mso-bidi-theme-font:minor-latin'>Make new
    … …  
    23022302centering operations as given by the BNS nomenclature. This can be needed if
    23032303one had discovered a requirement of doubling a cell axis in the previous step
    2304 (e.g. a nonzero propagation vector). This is not required in this case and we are
    2305 using the space group (<span class=SpellE>Pnma</span>) for the magnetic cell.
    2306 Leave the box at the bottom about constraints checked as we want them to tie
    2307 the two phases together.<span style='mso-spacerun:yes'>  </span>Press <b
     2304(e.g. a nonzero propagation vector). This is not required in this case and we
     2305are using the space group (<span class=SpellE>Pnma</span>) for the magnetic
     2306cell. Leave the box at the bottom about constraints checked as we want them to
     2307tie the two phases together.<span style='mso-spacerun:yes'>  </span>Press <b
    23082308style='mso-bidi-font-weight:normal'><span style='font-family:"Calibri",sans-serif;
    23092309mso-ascii-theme-font:minor-latin;mso-hansi-theme-font:minor-latin;mso-bidi-theme-font:
    … …  
    23292329 <v:imagedata src="SimpleMagnetic_files/image035.png" o:title=""/>
    23302330</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=360
    2331 src="SimpleMagnetic_files/image032.png" v:shapes="_x0000_i1080"><![endif]></span></p>
     2331src="SimpleMagnetic_files/image092.png" v:shapes="_x0000_i1080"><![endif]></span></p>
    23322332
    23332333<p class=MsoNormal>The phase is named with “mag” appended to the end, the phase
    … …  
    23452345 <v:imagedata src="SimpleMagnetic_files/image037.png" o:title=""/>
    23462346</v:shape><![endif]--><![if !vml]><img border=0 width=517 height=353
    2347 src="SimpleMagnetic_files/image033.png" v:shapes="_x0000_i1079"><![endif]></span></p>
     2347src="SimpleMagnetic_files/image093.png" v:shapes="_x0000_i1079"><![endif]></span></p>
    23482348
    23492349<p class=MsoNormal>This shows all the possible required constraints between the
    … …  
    23642364 <v:imagedata src="SimpleMagnetic_files/image039.png" o:title=""/>
    23652365</v:shape><![endif]--><![if !vml]><img border=0 width=515 height=186
    2366 src="SimpleMagnetic_files/image036.png" v:shapes="Picture_x0020_32"><![endif]></span></p>
    2367 
    2368 <p class=MsoNormal>This gives the constraints between the two phases for scale
    2369 factors (e.g. phase fractions) and the size &amp; mustrain sample broadening
    2370 terms. NB: this assumes isotropic modelling of both because the original LaMnO<sub>3</sub>
     2366src="SimpleMagnetic_files/image095.png" v:shapes="Picture_x0020_32"><![endif]></span></p>
     2367
     2368<p class=MsoNormal>This gives the constraints between the two phases for scale factors
     2369(e.g. phase fractions) and the size &amp; mustrain sample broadening terms. NB:
     2370this assumes isotropic modelling of both because the original LaMnO<sub>3</sub>
    23712371was modeled that way. If you want to use one of the more complex sample
    23722372broadening models, you will have to revisit this tab and put in the appropriate
    … …  
    23962396 <v:imagedata src="SimpleMagnetic_files/image041.png" o:title=""/>
    23972397</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=149
    2398 src="SimpleMagnetic_files/image038.png" v:shapes="Picture_x0020_23"><![endif]></span></p>
     2398src="SimpleMagnetic_files/image097.png" v:shapes="Picture_x0020_23"><![endif]></span></p>
    23992399
    24002400<p class=MsoNormal>The boxes that carry the magnetic moment components (<span
    … …  
    24312431 <v:imagedata src="SimpleMagnetic_files/image043.png" o:title=""/>
    24322432</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=308
    2433 src="SimpleMagnetic_files/image040.png" v:shapes="Picture_x0020_24"><![endif]></span></p>
     2433src="SimpleMagnetic_files/image098.png" v:shapes="Picture_x0020_24"><![endif]></span></p>
    24342434
    24352435<p class=MsoNormal>It now shows the magnetic space group as <span class=SpellE>Pn’ma</span>’.
    … …  
    24432443 <v:imagedata src="SimpleMagnetic_files/image045.png" o:title=""/>
    24442444</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=162
    2445 src="SimpleMagnetic_files/image042.png" v:shapes="Picture_x0020_25"><![endif]></span></p>
     2445src="SimpleMagnetic_files/image099.png" v:shapes="Picture_x0020_25"><![endif]></span></p>
    24462446
    24472447<p class=MsoNormal><span class=GramE>with</span> 0.0 in each of the magnetic
    … …  
    24872487 <v:imagedata src="SimpleMagnetic_files/image047.png" o:title=""/>
    24882488</v:shape><![endif]--><![if !vml]><img border=0 width=421 height=307
    2489 src="SimpleMagnetic_files/image044.png" v:shapes="Picture_x0020_26"><![endif]></span></p>
     2489src="SimpleMagnetic_files/image100.png" v:shapes="Picture_x0020_26"><![endif]></span></p>
    24902490
    24912491<p class=MsoNormal>Under the <b style='mso-bidi-font-weight:normal'><span
    … …  
    25022502 <v:imagedata src="SimpleMagnetic_files/image049.png" o:title=""/>
    25032503</v:shape><![endif]--><![if !vml]><img border=0 width=444 height=225
    2504 src="SimpleMagnetic_files/image046.png" v:shapes="Picture_x0020_34"><![endif]></span></p>
     2504src="SimpleMagnetic_files/image101.png" v:shapes="Picture_x0020_34"><![endif]></span></p>
    25052505
    25062506<p class=MsoNormal>Scroll down to the bottom and select <b style='mso-bidi-font-weight:
    … …  
    25182518 <v:imagedata src="SimpleMagnetic_files/image051.png" o:title=""/>
    25192519</v:shape><![endif]--><![if !vml]><img border=0 width=416 height=303
    2520 src="SimpleMagnetic_files/image048.png" v:shapes="Picture_x0020_35"><![endif]></span></p>
     2520src="SimpleMagnetic_files/image102.png" v:shapes="Picture_x0020_35"><![endif]></span></p>
    25212521
    25222522<p class=MsoNormal>Now return to phases and select <b style='mso-bidi-font-weight:
    … …  
    25332533 <v:imagedata src="SimpleMagnetic_files/image053.png" o:title=""/>
    25342534</v:shape><![endif]--><![if !vml]><img border=0 width=489 height=101
    2535 src="SimpleMagnetic_files/image050.png" v:shapes="Picture_x0020_37"><![endif]></span></p>
     2535src="SimpleMagnetic_files/image103.png" v:shapes="Picture_x0020_37"><![endif]></span></p>
    25362536
    25372537<p class=MsoNormal>The least squares will not begin a refinement of <span
    … …  
    25542554 <v:imagedata src="SimpleMagnetic_files/image055.png" o:title=""/>
    25552555</v:shape><![endif]--><![if !vml]><img border=0 width=618 height=567
    2556 src="SimpleMagnetic_files/image052.png" v:shapes="Picture_x0020_30"><![endif]></span></p>
     2556src="SimpleMagnetic_files/image105.png" v:shapes="Picture_x0020_30"><![endif]></span></p>
    25572557
    25582558<p class=MsoNormal>There does not appear to be any calculated magnetic
    … …  
    25652565 <v:imagedata src="SimpleMagnetic_files/image057.png" o:title=""/>
    25662566</v:shape><![endif]--><![if !vml]><img border=0 width=618 height=567
    2567 src="SimpleMagnetic_files/image054.png" v:shapes="Picture_x0020_31"><![endif]></span></p>
     2567src="SimpleMagnetic_files/image107.png" v:shapes="Picture_x0020_31"><![endif]></span></p>
    25682568
    25692569<p class=MsoNormal>The magnetic moment is clearly too small; to let the least
    … …  
    25782578
    25792579<p class=MsoNormal><span style='mso-no-proof:yes'><!--[if gte vml 1]><v:shape
    2580  id="Picture_x0020_40" o:spid="_x0000_i1068" type="#_x0000_t75" style='width:463.5pt;
    2581  height:426pt;visibility:visible;mso-wrap-style:square'>
     2580 id="_x0000_i1068" type="#_x0000_t75" style='width:463.5pt;height:426pt;
     2581 visibility:visible;mso-wrap-style:square'>
    25822582 <v:imagedata src="SimpleMagnetic_files/image059.png" o:title=""/>
    25832583</v:shape><![endif]--><![if !vml]><img border=0 width=618 height=568
    2584 src="SimpleMagnetic_files/image056.png" v:shapes="Picture_x0020_40"><![endif]></span></p>
     2584src="SimpleMagnetic_files/image108.png" v:shapes="_x0000_i1068"><![endif]></span></p>
    25852585
    25862586<p class=MsoNormal>This appears to be a reasonable solution; a more complete
    … …  
    26112611 <v:imagedata src="SimpleMagnetic_files/image061.png" o:title=""/>
    26122612</v:shape><![endif]--><![if !vml]><img border=0 width=621 height=351
    2613 src="SimpleMagnetic_files/image058.png" v:shapes="Picture_x0020_33"><![endif]></span></p>
     2613src="SimpleMagnetic_files/image109.png" v:shapes="Picture_x0020_33"><![endif]></span></p>
    26142614
    26152615<p class=MsoNormal>Now set the spin operators to all “<b style='mso-bidi-font-weight:
    … …  
    26262626 <v:imagedata src="SimpleMagnetic_files/image063.png" o:title=""/>
    26272627</v:shape><![endif]--><![if !vml]><img border=0 width=619 height=124
    2628 src="SimpleMagnetic_files/image060.png" v:shapes="Picture_x0020_18"><![endif]></span></p>
     2628src="SimpleMagnetic_files/image113.png" v:shapes="Picture_x0020_18"><![endif]></span></p>
    26292629
    26302630<p class=MsoNormal>Again, one can make the same argument that since the 010
    … …  
    26562656 <v:imagedata src="SimpleMagnetic_files/image065.png" o:title=""/>
    26572657</v:shape><![endif]--><![if !vml]><img border=0 width=619 height=568
    2658 src="SimpleMagnetic_files/image062.png" v:shapes="Picture_x0020_19"><![endif]></span></p>
     2658src="SimpleMagnetic_files/image115.png" v:shapes="Picture_x0020_19"><![endif]></span></p>
    26592659
    26602660<p class=MsoNormal>There is intensity in the lowest angle reflection (the 010)
    … …  
    26792679 <v:imagedata src="SimpleMagnetic_files/image104.png" o:title=""/>
    26802680</v:shape><![endif]--><![if !vml]><img border=0 width=612 height=251
    2681 src="SimpleMagnetic_files/image064.png" v:shapes="Picture_x0020_20"><![endif]></span></p>
     2681src="SimpleMagnetic_files/image116.png" v:shapes="Picture_x0020_20"><![endif]></span></p>
    26822682
    26832683<p class=MsoNormal><span style='mso-no-proof:yes'><!--[if gte vml 1]><v:shape
    … …  
    26862686 <v:imagedata src="SimpleMagnetic_files/image106.png" o:title=""/>
    26872687</v:shape><![endif]--><![if !vml]><img border=0 width=610 height=235
    2688 src="SimpleMagnetic_files/image066.png" v:shapes="Picture_x0020_21"><![endif]></span></p>
     2688src="SimpleMagnetic_files/image117.png" v:shapes="Picture_x0020_21"><![endif]></span></p>
    26892689
    26902690<p class=MsoNormal>You can see in particular at the pair of peaks at 33.3 and
    … …  
    27122712 <v:imagedata src="SimpleMagnetic_files/image110.png" o:title=""/>
    27132713</v:shape><![endif]--><![if !vml]><img border=0 width=606 height=528
    2714 src="SimpleMagnetic_files/image068.png" v:shapes="Picture_x0020_38"><![endif]></span></p>
     2714src="SimpleMagnetic_files/image118.png" v:shapes="Picture_x0020_38"><![endif]></span></p>
    27152715
    27162716<p class=MsoNormal>Looking at the plot, it would seem that the lattice
    … …  
    27352735 <v:imagedata src="SimpleMagnetic_files/image114.png" o:title=""/>
    27362736</v:shape><![endif]--><![if !vml]><img border=0 width=479 height=317
    2737 src="SimpleMagnetic_files/image070.png" v:shapes="Picture_x0020_39"><![endif]></span></p>
     2737src="SimpleMagnetic_files/image122.png" v:shapes="Picture_x0020_39"><![endif]></span></p>
    27382738
    27392739<p class=MsoNormal>Since the scan covers a very wide range in 2<span
    … …  
    27672767
    27682768<p class=MsoNormal><span style='mso-no-proof:yes'><!--[if gte vml 1]><v:shape
    2769  id="_x0000_i1060" type="#_x0000_t75" style='width:465pt;height:404.25pt;
    2770  visibility:visible;mso-wrap-style:square'>
     2769 id="Picture_x0020_40" o:spid="_x0000_i1060" type="#_x0000_t75" style='width:465pt;
     2770 height:404.25pt;visibility:visible;mso-wrap-style:square'>
    27712771 <v:imagedata src="SimpleMagnetic_files/image072.png" o:title=""/>
    27722772</v:shape><![endif]--><![if !vml]><img border=0 width=620 height=539
    2773 src="SimpleMagnetic_files/image073.png" v:shapes="_x0000_i1060"><![endif]></span></p>
     2773src="SimpleMagnetic_files/image123.png" v:shapes="Picture_x0020_40"><![endif]></span></p>
    27742774
    27752775<p class=MsoNormal>Now we can add refinement of the atom positions and thermal
    … …  
    28242824 <v:imagedata src="SimpleMagnetic_files/image121.png" o:title=""/>
    28252825</v:shape><![endif]--><![if !vml]><img border=0 width=615 height=527
    2826 src="SimpleMagnetic_files/image074.png" v:shapes="Picture_x0020_41"><![endif]></span></p>
     2826src="SimpleMagnetic_files/image124.png" v:shapes="Picture_x0020_41"><![endif]></span></p>
    28272827
    28282828<p class=MsoNormal>This curve shows a couple of peaks which are from some
    … …  
    28582858 <v:imagedata src="SimpleMagnetic_files/image111.png" o:title=""/>
    28592859</v:shape><![endif]--><![if !vml]><img border=0 width=615 height=129
    2860 src="SimpleMagnetic_files/image075.png" v:shapes="Picture_x0020_42"><![endif]></span></p>
     2860src="SimpleMagnetic_files/image125.png" v:shapes="Picture_x0020_42"><![endif]></span></p>
    28612861
    28622862<p class=MsoNormal><o:p>&nbsp;</o:p></p>
    … …  
    28762876 <v:imagedata src="SimpleMagnetic_files/image119.png" o:title=""/>
    28772877</v:shape><![endif]--><![if !vml]><img border=0 width=616 height=247
    2878 src="SimpleMagnetic_files/image076.png" v:shapes="Picture_x0020_44"><![endif]></span></p>
     2878src="SimpleMagnetic_files/image131.png" v:shapes="Picture_x0020_44"><![endif]></span></p>
    28792879
    28802880<p class=MsoNormal>The plot will show the unit cell contents of <span
    … …  
    28892889 <v:imagedata src="SimpleMagnetic_files/image126.png" o:title=""/>
    28902890</v:shape><![endif]--><![if !vml]><img border=0 width=610 height=513
    2891 src="SimpleMagnetic_files/image077.png" v:shapes="Picture_x0020_45"><![endif]></span></p>
     2891src="SimpleMagnetic_files/image132.png" v:shapes="Picture_x0020_45"><![endif]></span></p>
    28922892
    28932893<p class=MsoNormal>This completes this tutorial; you can save the project if
    … …  
    29992999 <v:imagedata src="SimpleMagnetic_files/image067.png" o:title=""/>
    30003000</v:shape><![endif]--><![if !vml]><img border=0 width=261 height=276
    3001 src="SimpleMagnetic_files/image079.png" v:shapes="Picture_x0020_27"><![endif]></span></p>
     3001src="SimpleMagnetic_files/image133.png" v:shapes="Picture_x0020_27"><![endif]></span></p>
    30023002
    30033003<p class=MsoNormal style='margin-left:.25in'><span class=GramE>and</span> the
    … …  
    30093009 <v:imagedata src="SimpleMagnetic_files/image069.png" o:title=""/>
    30103010</v:shape><![endif]--><![if !vml]><img border=0 width=596 height=543
    3011 src="SimpleMagnetic_files/image094.png" v:shapes="Picture_x0020_28"><![endif]></span></p>
     3011src="SimpleMagnetic_files/image135.png" v:shapes="Picture_x0020_28"><![endif]></span></p>
    30123012
    30133013<h3>Step 2: Select Limits </h3>
    … …  
    30443044 <v:imagedata src="SimpleMagnetic_files/image071.png" o:title=""/>
    30453045</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=568
    3046 src="SimpleMagnetic_files/image096.png" v:shapes="Picture_x0020_29"><![endif]></span></p>
     3046src="SimpleMagnetic_files/image137.png" v:shapes="Picture_x0020_29"><![endif]></span></p>
    30473047
    30483048<h3><a name="sucrose_peak_fit"></a>Step 3: Read in the chemical structure for
    … …  
    31133113 <v:imagedata src="SimpleMagnetic_files/image134.png" o:title=""/>
    31143114</v:shape><![endif]--><![if !vml]><img border=0 width=280 height=224
    3115 src="SimpleMagnetic_files/image112.png" v:shapes="Picture_x0020_46"><![endif]></span></p>
     3115src="SimpleMagnetic_files/image139.png" v:shapes="Picture_x0020_46"><![endif]></span></p>
    31163116
    31173117<p class=MsoNormal style='margin-left:.25in'>Select the histogram (or press <b
    … …  
    31273127 <v:imagedata src="SimpleMagnetic_files/image136.png" o:title=""/>
    31283128</v:shape><![endif]--><![if !vml]><img border=0 width=598 height=304
    3129 src="SimpleMagnetic_files/image120.png" v:shapes="Picture_x0020_47"><![endif]></span></p>
     3129src="SimpleMagnetic_files/image161.png" v:shapes="Picture_x0020_47"><![endif]></span></p>
    31303130
    31313131<p class=MsoNormal style='margin-left:.25in'>Notice that the space group from
    … …  
    31513151 <v:imagedata src="SimpleMagnetic_files/image138.png" o:title=""/>
    31523152</v:shape><![endif]--><![if !vml]><img border=0 width=622 height=221
    3153 src="SimpleMagnetic_files/image127.png" v:shapes="Picture_x0020_48"><![endif]></span></p>
     3153src="SimpleMagnetic_files/image162.png" v:shapes="Picture_x0020_48"><![endif]></span></p>
    31543154
    31553155<p class=MsoListParagraphCxSpFirst style='margin-left:0in;mso-add-space:auto'>This
    … …  
    31763176 <v:imagedata src="SimpleMagnetic_files/image143.png" o:title=""/>
    31773177</v:shape><![endif]--><![if !vml]><img border=0 width=622 height=221
    3178 src="SimpleMagnetic_files/image128.png" v:shapes="Picture_x0020_49"><![endif]></span><br
     3178src="SimpleMagnetic_files/image163.png" v:shapes="Picture_x0020_49"><![endif]></span><br
    31793179style='mso-special-character:line-break'>
    31803180<![if !supportLineBreakNewLine]><br style='mso-special-character:line-break'>
    … …  
    31823182
    31833183<p class=MsoNormal><span class=GramE>showing</span> the lattice constants for
    3184 LaCaMnO<sub>3</sub> you had obtained from the <span class=SpellE>cif</span> file.
    3185 Note that the space group is set to that of the <span class=SpellE>Bravais</span>
     3184LaCaMnO<sub>3</sub> you had obtained from the <span class=SpellE>cif</span>
     3185file. Note that the space group is set to that of the <span class=SpellE>Bravais</span>
    31863186lattice (P m <span class=SpellE>m</span> m) and not the space group for LaCaMnO<sub>3</sub>
    31873187(P b n m).</p>
    … …  
    31983198 <v:imagedata src="SimpleMagnetic_files/image145.png" o:title=""/>
    31993199</v:shape><![endif]--><![if !vml]><img border=0 width=621 height=436
    3200 src="SimpleMagnetic_files/image129.png" v:shapes="Picture_x0020_50"><![endif]></span></p>
     3200src="SimpleMagnetic_files/image164.png" v:shapes="Picture_x0020_50"><![endif]></span></p>
    32013201
    32023202<p class=MsoListParagraphCxSpLast style='margin-left:0in;mso-add-space:auto'>Note
    … …  
    32053205also a few seemingly misplaced unindexed lines (at 37.4, 53.9 &amp;
    3206320667.4°2&#920;); probably some contaminating minor phase. We’ll have to ignore
    3207 them. Change the space group to <span class=SpellE>Pbnm</span>; the indexing will
    3208 change.</p>
     3207them. Change the space group to <span class=SpellE>Pbnm</span>; the indexing
     3208will change.</p>
    32093209
    32103210<p class=MsoNormal><span style='mso-no-proof:yes'><!--[if gte vml 1]><v:shape
    … …  
    32133213 <v:imagedata src="SimpleMagnetic_files/image147.png" o:title=""/>
    32143214</v:shape><![endif]--><![if !vml]><img border=0 width=625 height=439
    3215 src="SimpleMagnetic_files/image130.png" v:shapes="Picture_x0020_51"><![endif]></span><br>
     3215src="SimpleMagnetic_files/image165.png" v:shapes="Picture_x0020_51"><![endif]></span><br>
    32163216Then check the box <b style='mso-bidi-font-weight:normal'><span
    32173217style='font-family:"Calibri",sans-serif;mso-ascii-theme-font:minor-latin;
    … …  
    32263226 <v:imagedata src="SimpleMagnetic_files/image149.png" o:title=""/>
    32273227</v:shape><![endif]--><![if !vml]><img border=0 width=623 height=199
    3228 src="SimpleMagnetic_files/image140.png" v:shapes="Picture_x0020_52"><![endif]></span></p>
     3228src="SimpleMagnetic_files/image166.png" v:shapes="Picture_x0020_52"><![endif]></span></p>
    32293229
    32303230<p class=MsoListParagraphCxSpLast style='margin-left:0in;mso-add-space:auto'>Because
    … …  
    32453245
    32463246<p class=MsoNormal>In the previous step we did not have to resort to any
    3247 doubling of a cell axis to explain the suite of magnetic reflections, so the propagation
    3248 vector is zero (in case anyone asks!). To make the magnetic cell from the
    3249 chemical cell we will use the transform tool that is in GSAS-II in the General
    3250 tab for the chemical structure. That tab is</p>
     3247doubling of a cell axis to explain the suite of magnetic reflections, so the
     3248propagation vector is zero (in case anyone asks!). To make the magnetic cell
     3249from the chemical cell we will use the transform tool that is in GSAS-II in the
     3250General tab for the chemical structure. That tab is</p>
    32513251
    32523252<p class=MsoListParagraph style='margin-left:0in;mso-add-space:auto'><span
    … …  
    32563256 <v:imagedata src="SimpleMagnetic_files/image151.png" o:title=""/>
    32573257</v:shape><![endif]--><![if !vml]><img border=0 width=623 height=275
    3258 src="SimpleMagnetic_files/image141.png" v:shapes="Picture_x0020_53"><![endif]></span></p>
     3258src="SimpleMagnetic_files/image167.png" v:shapes="Picture_x0020_53"><![endif]></span></p>
    32593259
    32603260<p class=MsoNormal>Under the <b style='mso-bidi-font-weight:normal'><span
    … …  
    33083308 <v:imagedata src="SimpleMagnetic_files/image157.png" o:title=""/>
    33093309</v:shape><![endif]--><![if !vml]><img border=0 width=196 height=87
    3310 src="SimpleMagnetic_files/image146.png" v:shapes="Picture_x0020_56"><![endif]></span></p>
     3310src="SimpleMagnetic_files/image168.png" v:shapes="Picture_x0020_56"><![endif]></span></p>
    33113311
    33123312<p class=MsoNormal>This allows one to reject certain atoms that are known to
    … …  
    33233323 <v:imagedata src="SimpleMagnetic_files/image159.png" o:title=""/>
    33243324</v:shape><![endif]--><![if !vml]><img border=0 width=619 height=365
    3325 src="SimpleMagnetic_files/image148.png" v:shapes="Picture_x0020_57"><![endif]></span></p>
     3325src="SimpleMagnetic_files/image169.png" v:shapes="Picture_x0020_57"><![endif]></span></p>
    33263326
    33273327<p class=MsoNormal>The phase is named with “mag” appended to the end, the phase
    … …  
    33473347 <v:imagedata src="SimpleMagnetic_files/image170.png" o:title=""/>
    33483348</v:shape><![endif]--><![if !vml]><img border=0 width=625 height=143
    3349 src="SimpleMagnetic_files/image150.png" v:shapes="Picture_x0020_58"><![endif]></span></p>
     3349src="SimpleMagnetic_files/image171.png" v:shapes="Picture_x0020_58"><![endif]></span></p>
    33503350
    33513351<p class=MsoListParagraphCxSpMiddle style='margin-left:0in;mso-add-space:auto'>Notice
    … …  
    33743374 <v:imagedata src="SimpleMagnetic_files/image172.png" o:title=""/>
    33753375</v:shape><![endif]--><![if !vml]><img border=0 width=320 height=266
    3376 src="SimpleMagnetic_files/image152.png" v:shapes="Picture_x0020_60"><![endif]></span></p>
     3376src="SimpleMagnetic_files/image173.png" v:shapes="Picture_x0020_60"><![endif]></span></p>
    33773377
    33783378<p class=MsoListParagraphCxSpMiddle style='margin-left:0in;mso-add-space:auto'>The
    … …  
    33893389 <v:imagedata src="SimpleMagnetic_files/image174.png" o:title=""/>
    33903390</v:shape><![endif]--><![if !vml]><img border=0 width=634 height=133
    3391 src="SimpleMagnetic_files/image153.png" v:shapes="Picture_x0020_61"><![endif]></span></p>
     3391src="SimpleMagnetic_files/image177.png" v:shapes="Picture_x0020_61"><![endif]></span></p>
    33923392
    33933393<p class=MsoListParagraphCxSpLast style='margin-left:0in;mso-add-space:auto'>If
    … …  
    34453445 <v:imagedata src="SimpleMagnetic_files/image176.png" o:title=""/>
    34463446</v:shape><![endif]--><![if !vml]><img border=0 width=692 height=486
    3447 src="SimpleMagnetic_files/image154.png" v:shapes="Picture_x0020_64"><![endif]></span></p>
     3447src="SimpleMagnetic_files/image181.png" v:shapes="Picture_x0020_64"><![endif]></span></p>
    34483448
    34493449<p class=MsoListParagraphCxSpLast style='margin-left:0in;mso-add-space:auto'>Clearly
    … …  
    35163516 <v:imagedata src="SimpleMagnetic_files/image178.png" o:title=""/>
    35173517</v:shape><![endif]--><![if !vml]><img border=0 width=624 height=119
    3518 src="SimpleMagnetic_files/image155.png" v:shapes="Picture_x0020_63"><![endif]></span></p>
     3518src="SimpleMagnetic_files/image183.png" v:shapes="Picture_x0020_63"><![endif]></span></p>
    35193519
    35203520<p class=MsoNormal>Then do <b style='mso-bidi-font-weight:normal'><span
    … …  
    35293529 <v:imagedata src="SimpleMagnetic_files/image180.png" o:title=""/>
    35303530</v:shape><![endif]--><![if !vml]><img border=0 width=625 height=439
    3531 src="SimpleMagnetic_files/image156.png" v:shapes="Picture_x0020_65"><![endif]></span></p>
     3531src="SimpleMagnetic_files/image185.png" v:shapes="Picture_x0020_65"><![endif]></span></p>
    35323532
    35333533<p class=MsoNormal><span class=GramE>and</span> the magnetic moment components
    … …  
    35393539 <v:imagedata src="SimpleMagnetic_files/image182.png" o:title=""/>
    35403540</v:shape><![endif]--><![if !vml]><img border=0 width=628 height=123
    3541 src="SimpleMagnetic_files/image158.png" v:shapes="Picture_x0020_66"><![endif]></span></p>
     3541src="SimpleMagnetic_files/image187.png" v:shapes="Picture_x0020_66"><![endif]></span></p>
    35423542
    35433543<p class=MsoNormal>So we test the next possibility.</p>
    … …  
    35923592 <v:imagedata src="SimpleMagnetic_files/image184.png" o:title=""/>
    35933593</v:shape><![endif]--><![if !vml]><img border=0 width=630 height=442
    3594 src="SimpleMagnetic_files/image160.png" v:shapes="Picture_x0020_67"><![endif]></span></p>
     3594src="SimpleMagnetic_files/image189.png" v:shapes="Picture_x0020_67"><![endif]></span></p>
    35953595
    35963596<p class=MsoNormal>The <b style='mso-bidi-font-weight:normal'><span
    … …  
    36063606 <v:imagedata src="SimpleMagnetic_files/image186.png" o:title=""/>
    36073607</v:shape><![endif]--><![if !vml]><img border=0 width=630 height=118
    3608 src="SimpleMagnetic_files/image175.png" v:shapes="Picture_x0020_68"><![endif]></span></p>
     3608src="SimpleMagnetic_files/image191.png" v:shapes="Picture_x0020_68"><![endif]></span></p>
    36093609
    36103610<p class=MsoNormal>Let’s test the next one.</p>
    … …  
    36573657 <v:imagedata src="SimpleMagnetic_files/image188.png" o:title=""/>
    36583658</v:shape><![endif]--><![if !vml]><img border=0 width=629 height=441
    3659 src="SimpleMagnetic_files/image179.png" v:shapes="Picture_x0020_69"><![endif]></span></p>
     3659src="SimpleMagnetic_files/image193.png" v:shapes="Picture_x0020_69"><![endif]></span></p>
    36603660
    36613661<p class=MsoNormal>The <b style='mso-bidi-font-weight:normal'><span
    … …  
    36703670 <v:imagedata src="SimpleMagnetic_files/image190.png" o:title=""/>
    36713671</v:shape><![endif]--><![if !vml]><img border=0 width=630 height=126
    3672 src="SimpleMagnetic_files/image194.png" v:shapes="Picture_x0020_70"><![endif]></span></p>
     3672src="SimpleMagnetic_files/image200.png" v:shapes="Picture_x0020_70"><![endif]></span></p>
    36733673
    36743674<p class=MsoNormal>We should now check the last spin configuration.</p>
    … …  
    37193719 <v:imagedata src="SimpleMagnetic_files/image192.png" o:title=""/>
    37203720</v:shape><![endif]--><![if !vml]><img border=0 width=633 height=444
    3721 src="SimpleMagnetic_files/image195.png" v:shapes="Picture_x0020_71"><![endif]></span></p>
     3721src="SimpleMagnetic_files/image201.png" v:shapes="Picture_x0020_71"><![endif]></span></p>
    37223722
    37233723<p class=MsoNormal><span class=GramE>and</span> with the strong <span
    … …  
    37303730 <v:imagedata src="SimpleMagnetic_files/image206.png" o:title=""/>
    37313731</v:shape><![endif]--><![if !vml]><img border=0 width=636 height=108
    3732 src="SimpleMagnetic_files/image196.png" v:shapes="Picture_x0020_72"><![endif]></span></p>
     3732src="SimpleMagnetic_files/image202.png" v:shapes="Picture_x0020_72"><![endif]></span></p>
    37333733
    37343734<p class=MsoNormal><o:p>&nbsp;</o:p></p>
    … …  
    37613761well. The do <b style='mso-bidi-font-weight:normal'><span style='font-family:
    37623762"Calibri",sans-serif;mso-ascii-theme-font:minor-latin;mso-hansi-theme-font:
    3763 minor-latin;mso-bidi-theme-font:minor-latin'>Calculate/Refine</span></b> for
    3764 each one. After several cycles of refinement I find the “<span class=SpellE>rrb</span>”
     3763minor-latin;mso-bidi-theme-font:minor-latin'>Calculate/Refine</span></b> for each
     3764one. After several cycles of refinement I find the “<span class=SpellE>rrb</span>”
    37653765model <span class=SpellE>Rwp</span>=7.615%, the “<span class=SpellE>rbr</span>”
    37663766model <span class=SpellE>Rwp</span>=7.716% and the “<span class=SpellE>brr</span>”
    … …  
    37933793 <v:imagedata src="SimpleMagnetic_files/image209.png" o:title=""/>
    37943794</v:shape><![endif]--><![if !vml]><img border=0 width=317 height=681
    3795 src="SimpleMagnetic_files/image197.png" v:shapes="Picture_x0020_73"><![endif]><!--[if gte vml 1]><v:shape
     3795src="SimpleMagnetic_files/image203.png" v:shapes="Picture_x0020_73"><![endif]><!--[if gte vml 1]><v:shape
    37963796 id="Picture_x0020_74" o:spid="_x0000_i1026" type="#_x0000_t75" style='width:239.25pt;
    37973797 height:510pt;visibility:visible;mso-wrap-style:square'>
    37983798 <v:imagedata src="SimpleMagnetic_files/image211.png" o:title=""/>
    37993799</v:shape><![endif]--><![if !vml]><img border=0 width=319 height=680
    3800 src="SimpleMagnetic_files/image198.png" v:shapes="Picture_x0020_74"><![endif]></span></p>
     3800src="SimpleMagnetic_files/image204.png" v:shapes="Picture_x0020_74"><![endif]></span></p>
    38013801
    38023802<p class=MsoNormal>The magnetic peaks contributing to this peak are the 200,221
    … …  
    38143814 <v:imagedata src="SimpleMagnetic_files/image213.png" o:title=""/>
    38153815</v:shape><![endif]--><![if !vml]><img border=0 width=632 height=669
    3816 src="SimpleMagnetic_files/image199.png" v:shapes="Picture_x0020_75"><![endif]></span></p>
     3816src="SimpleMagnetic_files/image205.png" v:shapes="Picture_x0020_75"><![endif]></span></p>
    38173817
    38183818<p class=MsoNormal><span class=GramE>which</span> shows that the ferromagnetic
Note: See TracChangeset for help on using the changeset viewer.