Powder X-ray Diffraction

Powder X-ray Diffraction

  • w.s.l. Boyer added an answer:
    Can someone give advice about XRD rocking-curve issue?

    When I measure rocking-curve of (111) reflection of 100nm-thick Pt thin films deposited at high temperature on Si-SiO2 substrates, the rocking-curve has its classical shape with a FWHM of about 1-1.5° (Figure 1).

    Due to technical problem, I had to change the way to deposit Pt films and I have now to deposit at room temperature and anneal under air in a conventional furnace. The shape of the rocking-curve is completely different (Figure 2).

    As I have never seen this before, can someone try to explain me?

    Thank you

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    w.s.l. Boyer

    I agree with Mark O Rikel:

    "The asymmetry of the rocking curve does not say much about crystallinity, but as Hans-Ulrich wrote, more grains are oriented not parallel to the surface in the 'positive' direction."

    I suspect those talking about amorphous peaks or not fully crystalline are forgetting that it is a rocking curve.  If a scan in 2theta looked like that, it might be an overlap of sharp Bragg peak (from larger 1000 nm crystals), broad Bragg peak (from nanocrystals) and/or amorphous peak.  But it is not a 2theta scan, it is a non-crystalline portions just won't show up (or will just be background).

    If you can get some additional data, I suggest double-checking that the acceptance angle covers the whole peak, even at the maximum tilts in both directions.

    Also, try repeating the rocking curve with the sample rotated 90 and 180 degrees from original setting.  If the amorphous or partially crystalline suggestions are true, the curve will stay the same no matter the orientation (I don't expect this).  If the sample has grains not oriented parallel to surface, the tail (asymmetry direction) will follow the sample orientation (I think this is likely).  The latter might be expected because the lower temperature deposition allows less atomic rearrangement to align with the substrate after the atoms impact the surface.  Thus, any small deviation from atoms arriving perpendicular to the surface will have an effect on the sample microstructure at low temperature, but not at high temperature.  Does that make sense to you?

  • Bhavya G. added an answer:
    Is it possible to know the compound by powder XRD pattern analysis?

    The pure precipitated unknown compound obtained as  the result of bacterial cellular mechanism was subjected to XRD study, result's is indicating the crystalline nature. here we are intrested to known its chemical composition.

    1. Is it possible to known?

    2. Is there is any software, which is user friendly for analysis....?

    3. what are other techiques we can approch for ?

    Thank you 

    Bhavya G.

    Thank you for your valuable  suggestion... 

  • P. Grima Gallardo added an answer:
    If I need to calculate the crystallite size with the Scherrer Equation, how can I choose its peak?

    1) If I need to calculate the crystallite size with the Scherrer Equation, how can I choose its peak? 

    2) In the Scherrer Equation d = (k * lamda) / (FWHM * cos (2theta) ), the FWHM value is Full Width at Half Maximum, but in the Excel spreadsheet containing the Scherrer's Equation (see the attachment), they calculate d by replacing FWHM with [ FWHM (structural) = FWHM (observed ) - FWHM (standard) ].

    Could someone please explain this replacement? I also don't know how to find the ref value needed for FWHM (standard).

    Thanks in advance!

    P. Grima Gallardo

    I agree with the excellent previous given answers, however I want to express my opinion. The FWHM of the diffraction peaks is the convolution of the detector and sample response, given by equation:


    where (FWHM)obs are the observed values, (FWHM)elect is the noise term which comes mainly from the amplification system and (2.35^2 Fe) comes from the hole creation statistics. F is the Fano factor (near to 0.1 for Ge detectors at 77K), e is a term which relates the energy to the number of free carriers created in the process and has a value of 2.9 eV for Ge detectors and E is the energy in keV.

  • Ravi Ananth added an answer:
    When using the Debye-Scherrer equation for calculating particle size (D=Kλ/(β cos θ) does one have to halve the FWHM(β)? Must all angles be in Radians?
    The Debye-Scherrer method is used to obtain X-ray diffraction measurements in powders.This method is applicable to crystallites ranging from 1.0 to 0.01 μm in diameter, but the grains must have good crystallinity.
    Ravi Ananth
    • "The functional from of the two equations is the same". Thanks Matt!
    • "FWHM of the peak measured in 2theta", because most diffractograms are coupled Omega-2Theta scans.
    • Is it possible to apply this formula for various (hkl)'s at multiple θ's  and get a feel for the shape of the "particle"?
  • Anwar M Rana added an answer:
    What free software do you use to analyze XRD data?
    There is many free software to analyze XRD data but what is the best, if I have raw, dat, cpi, sd , rd data?
    Anwar M Rana

    Mr. Piyush J. Patel, I dont think the software PowderX is free. However, its good to use for XRD analysis.

  • Alberto Martinelli added an answer:
    How can one estimate the type of an unknown atom by refining the occupancy of that atom during the Rietveld structure refinement?

    If the original unit cell (containing A,B and C atoms) is doped with D and E atoms for example, and we have found some possible atomic sites for an unknown atom, how is tit possible to understand the type of the unknown atom (whether it is D dopant or E dopant or even non of them) by refining its occupancy?

    Alberto Martinelli

    if you have a synthetic pure compound you know the exact amount of the different atomic species, so it is quite easy to check what is the best structural model. in addition you stated that E is a light element, whereas D seems the heaviest one in your phase; so it is highly unikely that they both occupy the same site. for example you guess that D substitutes A: then you can prepare a structural model accordingly (that is with the nominal content of A and D at the same atomic site) and see if the refinement improves (peak fit, R-factors) to confirm.

  • Ravi Ananth added an answer:
    XRD: can I quantify the ratio of two components in a sample from the intensities of the XRD reflexes?

    I have a sample consisting of Ir and IrO2. The XRD-pattern shows the reflexes of both components with similar intensities of the respective main peaks. Peaks are of comparable width.

    Do I have a chance to roughly quantify from the peak intensity ratio, the molar ratio of these two components in the sample?

    Ravi Ananth

    How do they account for the effect of "preferred orientation" and variations of the "Relative Intensity Ratio" as a result of particle size/strain/shape etc.?

  • Ravi Ananth added an answer:
    How can i measure relative crystallinity % for x-ray diffraction?
    Relative crystallinity was defined as the ratio of the peak area to the total area of a diffractogram (which is the sum of peak areas and amorphous areas) expressed as a percent By using origin pro how can i measure area under crystalline peaks and compared to total areas?
    Ravi Ananth

     Good reference Wissam! Thanks!

    All they need to do now is to extend the analyses from the conventional 1D equatorial diffractogram to a 2D diffractogram invariably involving some extent of "preferred orientation" convoluted in the XRD signal. Calibration with "known standards" would help "relative % crystallinity" detection. Consistent sample prep would be key in any such endeavor along with WPPM concepts to deconvolute individual constituent XRD signal :-)

    See example of Kevlar & Aluminum below. I'd be interested in such publications of similar analyses with 2D diffractograms if and when you have any.

  • Thang Quang Do added an answer:
    Can anybody help me to solve the powder XRD of MNPs which were synthesized by hydrothermal method? (attached XRD spectra)

    I have prepared MNPs (expected CuFe2O4) from aq. solutions of FeCl3 (1 eq) and CuCl2 (0.5 eq), urea (10 eq), glucose (10 mol%), and 30% aq NH3 (10 mL), ethgylene glycol (10 mL) by hydrothermal  method at 180 oC, for 8h. There are two possibilities to form either carbon coated CuFe2O4 or CuO/Carbon/Fe3O4 NPs.

    The mechanism for formation of CuO/Carbon/Fe3O4 might be as follows: The glucose can reduce Fe(III) to Fe(II) to form carbon coated Fe3O4 followed by stabilization of insitue generated CuO from CuCl2 in presence of basic medium (aq. NH3).

    or Carbon coated CuFe2O4 can form from the reaction among FeCl3, CuCl2, glucose in presence of basic medium.

    Please help me to solve PXRD (attached) of this material.

    Thanks in advance

    Thang Quang Do

    This is the pattern of Fe2O3.

  • A. Márquez-Herrera added an answer:
    Why is there no peak for XRD analysis for CuGaO2 transparent thin film even after annealing?

    Im using RF sputtering deposition technique.The maximum temperature that i used for annealing is 500C, because temp more than that will affect the glass slide that i used as a substrate. The XRD pattern only show the amorphous pattern of the glass slide. Can someone please give me a reasons why? thank you

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    A. Márquez-Herrera

    I suggest to change the glass to quartz due Quartz materials is more transparent than glass in UV-Vis experiments (less 200 nm). Also you can use a higher temperature in quartz (about 1300° C). Finally, try to perform the DRX experiment in grazing incident angle.

  • Tomasz Jaroń added an answer:
    Why Cu Kalpha1 to Kalpha2 intensity ratio can be different than ca. 2:1?

    I have a problem with refinement of a powder pattern in which Kalpha1 and Kalpha2 peaks are quite well separated at higher angles (low FWHM). What is weird, the ratio of Kalpha1 to Kalpha2 peaks is ca. 3:1 (as judged by eye - see the attached picture). The refined intensity ratio (in GSAS2) is 3.045.

    Does anybody know why the intensity ratio is different that ca. 2:1?

    Also, the Kalpha2 peaks are slightly shifted. I have no idea how to refine this pattern (I am rather experienced here - have solved and refined dozens of structures...).

    Tomasz Jaroń

    Dear Ravi,

    Now the ratio of Kalpha and Kalpha2 peaks is visually around 2:1, and Rietveld refinement is possible.

  • Clifford Chafin added an answer:
    The band Gap happens because the diffraction "touch" in the Brillouin Zone?


    I'm study about band structure... and I read this:

    "We have noted that diffraction occurs when one end of a wave vector touches a Bragg plane. In the context of nearly free electrons, diffraction causes the E Vs k relationship to distort in the vicinity of the Bragg planes (or Brillouin zone boundaries). This distortion causes some of the energy levels to become forbidden to the nearly free electrons, which results in the presence of band gaps in the material."

    link: http://nptel.ac.in/courses/113106040/Lecture32.pdf

    And I read in different places.. but still don't understand why happen this gap because the diffraction.


    Clifford Chafin

    I have always hated these sorts of explanations and I understand why you find it confusing.  The actual band gaps are not well approximated by nearly free electron theory but by Green's function methods.  This implies the right way to think about what is going on here is that the states near the BZ are mixing more strongly in a correlated way so that there is a split.  What does this have to do with Bragg diffraction?  The edges of the zones are where Bragg diffraction occurs.  Does this mean that this diffraction "causes" the splitting?  I find this suggestion kind of a stretch.  What matters is that this is exactly where the interactions of the states is the largest so they can mix.
    The usual nearly free electron model makes more sense for neutral fermions in periodic optical potentials for ultracold gases.  At least here the necessity of treating electrons near the fermi surface as weakly interacting quasiparticles is not necessary.  Interestingly, we usually apply the nearly free electron theory to explain gaps that are not so near the fermi surface anyway where we don't expect the quasiparticle assumption to be valid. 

    Maybe you will like the optical analog better.  When light passes through a dielectric what "causes" the band gaps to open up?  One can view the diverging internal energy storage of the the electromagnetic wave near resonance as the driver of such forbidden frequencies in the spectrum.  Such frequencies can only generate evanescent waves.  I made a pretty picture of this in the paper below.  

  • Roman Nikolaevich Vasin added an answer:
    How can I find out the purity and particle size quantitatively from PXRD data?

    From the sharpness of peak we conclude whether it is amorphous or crystalline and from the appearance of extra peaks impurities are suggested. But these suggestions are qualitative. Could we establish a numerical value for the purity and particle size?

    Roman Nikolaevich Vasin

    There were some discussions on this matter already. Please, use the 'Search' functionality. E.g. https://www.researchgate.net/post/How_can_I_get_the_percent_of_crystallinity_from_Powder_XRD_data/1



    And a general advice - do not use Scherrer's equation, in 99% of cases it will provide you with meaningless results.

  • Igor P. Zibrov added an answer:
    Is it possible to find new crystal's cell parameters using powder XRD results?

    Is it possible to find new crystal's cell parameters using powder XRD results?

    Igor P. Zibrov

    It is not big problem if the symmetry is high (cubic, hex., tetrag., ortho), but if the symmetry is monoclinic or triclinic you need to remember two rules: 1-XRD data must be of a high quality (use only K alpha 1 irradiation); 2-you must be sure that your powder is a single phase. TREOR is an indexing program in EXPO, you can try it.

  • Ravi Ananth added an answer:
    Does anyone know how to send out "hand shake" signals from the Bruker diffractometers to an external device through any communication port?

    We are using a Bruker D8 diffractometer for XRD rocking curve analyses. We are interested in finding out the procedure for sending out Metadata parameters to an external device through any of the existing interfaces (USB, Serial or Parallel) during RSM observations and data collection. Please share your knowledge and experience when convenient. Thanks a million!

    + 3 more attachments

    Ravi Ananth

    Got full feedback control of the Bruker D8!

    Now we are ready for RSM's for each topographic Pixel/Voxel :-)

  • Ali Kaouk added an answer:
    How can I convert an XRD JADE (*.pid or *.raw) file into a file supported by X'Pert HighScore Plus?
    I have data obtained by rigaku rint XRD through JADE software. My data is in *.pid and *.raw format but unfortunately X'Pert HighScore Plus is not supporting both file format, so i I want to change file format of diffraction data. I have used MATCH software, but it done not helped.
    Ali Kaouk

    PowDLL  not installing on Windows 10. Asking for Microsoft .NET Framework 2 and I already have the newest one.

  • Shahin Khademinia added an answer:
    Can anyone help me to determine the crystal structure of a compound Bi2Mn2O7 via reitveld analysis? I attached a PXRD file (txt)

    I have used a reference from Abdul halim shaari

    Shahin Khademinia

    Hello, The work was performed by Dr. MURAT SERTKOL who is an expert in the field you can search his name in the site.

  • Saravanakumar Subramaniyan added an answer:
    What is the reason behind the change in d-spacing and crystal plane of ZnO nanoparticles, when the dopants of Mn and Ag ions added in the ZnO matrix?

    I have synthesized undoped, Mn and Ag-doped ZnO nanoparticles. The HR-TEM image indicated that the nanoparticles are structurally uniform and well-oriented lattice fringe of d-spacing around 0.23 nm, 0.25 nm and 0.28 nm for undoped, Mn and Ag-doped ZnO nanoparticles, respectively. The d-spacing values are corresponding to (101) plane for undoped and Mn-doped ZnO, whereas the Ag-doped ZnO samples related to (100) plane. What is the reason behind the change in d-spacing and crystal plane of ZnO nanoparticles, when the dopants of Mn and Ag ions added in the ZnO matrix?

    Saravanakumar Subramaniyan

    Due to higher ionic radius of Mn and Ag than Zn2+, d-spacing increases with respect to dopant concentration

  • Antonio Pereira Goncalves added an answer:
    How might I measure N and C atom positions in an iron lattice?

    Hello all,

    I'm struggling to find C and N atomic positions in Fe lattice of a Fe-N-C compound. I need to distinguish the atomic positions. I was wondering if HR-TEM or neutron diffraction can help?

    Antonio Pereira Goncalves

    For a polycrystalline material I would suggest neutron diffraction: it  will give for sure some useful information on the different atoms positions.

  • Ravi Ananth added an answer:
    Can anyone help explain a missing peak in XRD?

    I made some regenerated cellulose films which were characterized by XRD to study the crystallinity, scan speed used was 1.8°/min. The XRD pattern I obtained is not identical to what has previously been reported (see attached pic, left side-literature & right side- my result)

    Lit.showes that the diffraction peaks for RC appear at 21.6◦ (2 0 0), 19.9◦ (1 1 0) and 12.0◦ (11 0), however my sample is only showing two peaks, one at 12.1◦ and another one at 21.2. I am rather confused as to whether the missing peak diffused withe the other peak and resulted in just one broad peak or what?

    Another questions is as you can see in my result I have two peaks,  if I calculate the crystallinity using the deconvulation method I consider the peak at 12.1◦ to be the crystalline peak due to its sharpness and the other peak at 21.2 to be the amorphous peak due to its broad nature, is this correct? I mean to just use peak shape as a means to determine whether the peak is crystalline or not?

    Ravi Ananth

    Two variables that would affect conventional equatorial scan XRD patterns of fibrous samples are:

    1. Degree of crystallinity.
    2. Preferred orientation.

    Both these are nearly impossible to detect with a single conventional "equatorial" scan diffractogram using the ubiquitous 0D "point counter" as illustrated in the query.


    1. Use a 2D dental photographic film exposure in the transmission Laue mode to identify overall effects of both the above mentioned factors. See example below.
    2. Rotate the sample about its surface normal and repeat the conventional equatorial diffractogram to identify any potential effects of "preferred orientation".

    "Preferred orientation" is an inevitable consequence of even "bunching" several fibers together for the sample holder.


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  • Ravi Ananth added an answer:
    What would be the best way to mask a smallish area (1 x 1 cm) on a bulk metal sample for grazing incidence XRD?

    The solutions that we have thought of include:

    1) Cutting the 1 x 1 cm section out of the sample. However, this will introduce deformation therefore alter the region in question.

    2) Use an aperture to decrease the spot size. Although grazing incidence may still smear the spot size outside the 1x1 cm at low angles

    3) Use a physical mask but we cannot think of a suitable material.

    Ravi Ananth

    Interesting potential practical solutions!

    However, the correct method would be to use no mask or coatings but a well collimated parallel beam optics/geometry in combination with real time 2D XRD detector as we demonstrate in the RG posts referenced below. Topographic imaging with GISAXS?

    "Beam projection: Because of the grazing-incidence angle, the focused x-ray beam (e.g. 50 μm tall) is projected into a long stripe over the sample surface (e.g. a 50 μm beam at 0.1° incidence is projected to 29 mm). For many samples, this will in fact spill over the up/down-stream edges of the sample (i.e. over-illuminate the sample in the beam direction). This wide area illumination has the advantage of dramatically increasing the effective scattering volume, and thus the measured signal. This also inherently averages over a wide area, yielding data that is statistically representative of the entire film. (On the other hand, this wide-area probing has the disadvantage of making more local probing difficult in GISAXS.)" http://gisaxs.com/index.php/GISAXS

    How does low angle X-Ray diffraction (XRD) determine the mesoporosity of a material? - ResearchGate. Available from: https://www.researchgate.net/post/How_low_angle_XRD_explains_the_mesoporosity_of_a_material [accessed Jul 20, 2015].

    The small incidence angle creates a large (humongous) projection of the incident beam on the sample surface. This fact can be taken advantage of by placing the 2D detector plane (or photographic film) at an acute (shallow) angle to the diffracted beam, which would be so that both sample surface and detector surface are nearly parallel! As Daniel Lee points out, won't work with a 0D conventional "point counter". We may thus be able to get the true "topographic" GIXRD/GISAXS/GIXRR image! https://www.flickr.com/photos/85210325@N04/9311681113/in/album-72157632724094863/ Positions 2 & 3 in this figure. What do you think? I'm going to demonstrate this concept soon experimentally. Meanwhile, any of you many that have the advantage of a 2D XRD imaging device like the PANalytical PIXcel 3D, or the Vantec Series are more than welcome to beat me to it. Go :-)

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  • Daniel Lee added an answer:
    How can I use Rietveld method to solve the crystal structure of a powder material?
    I synthesized a powder material including B,C,N,O and H by microwave method. When I compare powder X-ray diffraction pattern to the literature, there is no match. How can I find atomic positions, crystal structure and cell parameters of the material? I also have High score plus program. Can somebody help me?
    Daniel Lee

    Into your raw data. Then perform a pawley fit and see the Charge flipping function in Hoghscore. After calculation as a function of Fobs, you will see a series if electron densities and its atomic coordinates. Now you can fisrtly select the most highest density. That would be a heavier atom in among your system. You need to index it as maybe cation element. Likewise repeat tehse steps until finished. Finally you are ready to start rietveld refinement with ipunt arbitary Biso(Debye-waller temp factor) as a starting point. Now you may have all of requirement to do rietveld refinement.


  • Farai Dziike added an answer:
    Is it possible to measure the pore width from powder x-ray diffraction pattern of a zeolite?

    I assume that the first peak base width will give the pore width of zeolites.  Mostly we are getting the information regarding the pore size of zeolite  from the first peak position.   Of course BET adsorption isotherm is the final.  However, the initial information regarding the pore size we can get from this.  What is your opinion  on this.

    Farai Dziike

    It maybe be measured by doing Low-angle PXRD at 2 theta range 2 - 5. A peak is generated with an intensity that when integrated, it will give you a value that approximates the respective pore size. All the same, this works for mesoporous powdered materials. However, further verification will need to be conducted eg HRTEM and BET.

  • Roman Nikolaevich Vasin added an answer:
    What are the changes in true unit cell volume when applying a macrostrain model?

    I'm stuck trying to understand the physical meaning of a model in MAUD that seems to describe my data really well. I have data on CeN (in the NaCl structure) in a diamond anvil cell, but the {200} reflections are shifted to lower angle compared to the {111}. Data and refinement without macrostrain is attached.

    Now, I find that using the WSODF model and refining the 230 and 120 coefficients makes the fit about as good as one could hope for (refinement also attached). I just don't really understand the following:

    1. If I calculate the macrostrain under the model options, do I just multiply that onto the three unit cell axes to get the "true" unit cell that I observe?

    2. If I do so, the values I get (a = b = 4.609 Å, c = 4.663 Å) then result in the same unit cell volume as the unstrained case (where a = 4.635 Å). Is this a coincidence?

    3. What is the physical picture of this strain model? It clearly doesn't break the cubic symmetry (the {200} should split if it did), but how does this agree with the strained unit cell parameters above?

    4. Am I overfitting the macrostrain?

    Cheers from a scientist battling with the physical meaning his model (don't we all).


    Notes for people who might actually look at the data:

    - The Cu is there on purpose as a pressure standard.

    - There is also some anisotropic broadening going on, with {200} being much narrower than {111}, but that does not confuse me so much. I don't know if I should be able to see a connection to the macrostrain.

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    Roman Nikolaevich Vasin


    As far as I know, Dr. Sébastien Merkel is the one who implemented the "Radial Diffraction in the DAC" model into MAUD, so probably you could ask him is it possible to apply it for the axial setup (there may be some limitations in the code). Anyway, as I recall the papers of Singh et al., they have considered some mixture of Voigt and Reuss models for the isotropic material. From looking in your data it seems that there are too few grains in it to consider the material isotropic (at the very least, and also to say that it is Voigt, Reuss, or some average), so once again the physics behind the model will be a bit lost. And you should probably enable the "Arbitrary texture" model to describe preferred orientations; this will to some degree take care of intensity variations due to 'graininess'.

    Also in this model (see the Appendix to Wenk et al. Powder diffraction 2014 paper) “Beta” is the angle between the sample Z axis and the maximum stress direction. “Alpha” is a rotation around Z. Stress models in MAUD always consider Z axis normal to the pole figure projection, so for your .par files this means that Z || incoming beam.

    And as Dr. Tarik Ömer Oğurtani noted earlier, the difference between 111 and 002 peaks positions is most likely due to some planar defects (if you are 100% sure in your instrument!).

  • Daniel Lee added an answer:
    Can any one help me to analyze an XRD pattern?

    I have no experience in XRD analysis. Can any one help me to analyze the attached XRD result.

    Daniel Lee

    diffraction intensity is too !!! low.

    What happened? Do you want to gain more intensity or what you want?

  • Rajesh Nayak added an answer:
    XRD software
    What is the best free software for the analysis of powder-XRD data?
    I have .raw and .doc(X-Y) data.
    Rajesh Nayak

    Please guide me to calculate inversion of spinel using fullprof. or suggest me better software if any

  • Ravi Ananth added an answer:
    I am trying to do Rietveld refinement using MAUD (materials analysis using diffraction) for X Ray data, for a homogenized ZN-12 Al sample - can anyone help?
    All the calculated intensities fit well except 2. Both intensities are of zinc phase(43.5 degrees and 54.5 degrees) I have tried scagliotti parameters, micro strain parameters, but no fitting doesn't improve. Can anyone help in this regard?
    Ravi Ananth

    It is amazing that all this pontification and discussion has lead us nowhere :-)

    The ambivalence of powder diffractometry doesn't seem to abate even after a century after the Braggs.

    The conclusion of "detector saturation" is astounding! Were the operator and user completely oblivious to such a blatantly obvious fact? That is flabbergasting coming from the great BHU well known for its long expertise in Metallurgy :-)

    • I see no experimental observation to isolate any effects of preferred orientation which is unavoidable to some degree in most practical situations.
    • "a homogenized ZN-12 Al sample" - What does that mean? Powder or bulk? If bulk (or powder), what is the sample surface morphology (flat, curved,???). What was the sample prep process used?
    • If the WPPM was used, then how was the effect of "preferred orientation" addressed?
    • Why is there no data from a powder standard or an annealed standard presented?
    • Why is there no attempt to identify the instrumental profile for the diffractometer? Does it not matter? What shape was used for the "fitting" process? is it prudent (or expedient?) to assume all (hkl)'s have the same shape?

    BTW please post the XRD data (attach to question if possible) as a text file or Excel file so that the rest of us can have some fun too, like Maykel :-)

  • Ravi Ananth added an answer:
    How can I overcome quartz peak's intensity in bulk mineralogy (powder sediment sample) XRD analysis?

    Powder XRD analysis.

    Ravi Ananth

    Good practical suggestions all!

    • Please post your data with all experimental details for the best feedback. Include any sample prep.
    • Do include additional topics (up to 15 total) to include other relevant topics like "XRD", "PXRD" etc to maximize circulation and participation. See attached posts for example.
    • Include a standard pattern for instrument calibration.
    • Get the pattern for just the "quartz" and try to deconvolute it from the data.
    • If you separate the constituents mechanically or otherwise, do get the diffractogram from both composites. The desired constituents and the undesirable ones :-)
    • Normalize the XRD data w.r.t. the total integrated intensity under the profile. This assumes that the packing density is identical and thus the diffracting volume remains unchanged.

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