What would be the X-ray diffraction intensity of a ternary compound with one atom spatially fluctuating inside the octahedra?

If a ternary ABC2 compound with two sublattices, say BC4 and AC8, where B and C are at the center of tetrahedra and octahedra respectively, suppose if A atom is randomly fluctuating inside the AC8...

23 January 2020 4,770 4 View

Is there a possibility of coupling between optical phonon and lone pair of electrons (lone pair electron-phonon coupling)?

The electron-phonon coupling is very common in condensed matter physics. But I am not sure if the same phenomenon is allowed between lone pair of electrons and phonon?.

26 November 2019 189 4 View

How to run a cmpr file with synchrotron data in dat format?

While I am uploading dat file in CMPR software, I don't see any peak list in my index menu. So I am unable to continue further for peak indexing. How to solve this issue?

20 March 2017 3,962 1 View

I have a high pressure data on EXAFS and I am a beginner on this topic. How to start EXAFS data analysis?

16 November 2016 3,208 3 View

How to reduce the chi square value of XRD pattern if its initial value is too high (10^7) by profile matching method?

I have solved the lattice type and space group of high pressure phase of a thallium based ternary ABC2 type compound which crystallizes in orthorhombic structure. I tried to fit the high pressure...

12 May 2016 6,369 23 View

Can I perform g_mmpbsa for protein-DNA complex? Will it give meaningful results?

In order to calculate the binding energy between protein and DNA, i run g_mmpbsa for my protein-DNA complex and i got big energy value number (-17894.45 kcal/mol). But i think the energy values...

18 November 2015 2,936 3 View

What is the procedure to run do_x3dna for gromacs 5 trajectory files?

Can anyone help me to run do_x3DNA (part of 3DNA tool) for GROMACS 5 trajectory files? I have installed it in a server, and run the command, and its showing segmentation error, so anyone who is...

22 February 2015 6,420 3 View

Is there any possible way to distinguish between ETT and TPQT from high pressure XRD, Raman and resistivity studies?

ARPES study is the direct evidence for the topological insulating state. However, some of the trivial insulators can be transformed into non-trivial topological insulators by alloying, applying...

03 February 2015 3,771 3 View

What could be the reason for not having further low chi square value (better agreement) in my refinement result?

I have tried every combination of parameter changes and after that i have a poor chi square value. I can't get it lower any further. I know there have been a lot of discussion about Rietveld...

26 February 2021 8,480 3 View

Why the CHi^2 is close to zero with a bad fitting but the Rp and Rwp are still high?

I am refining my XRD data using in FullProf program. The intensity of the modulated X-ray peaks is almost flat. I tried to adjust the peak intensities but unsuccessful. What is the reason? I guess...

23 February 2021 2,304 4 View

Why CHi^2 is reducing if I divide the intensity by a constant factor?

I was refining my XRD data in FullProf. Highest intensity was 400000. The fitting was good but still the Chi^2 value is very high (0.174E+04) I divided the intensity by some constant factor (say...

17 February 2021 3,383 5 View

Is it possible to do Reitveld Refinement on single crystal XRD data?

I tried to do single-crystal Rietveld Refinement on my single-crystal XRD data using the option "refinement on single-crystal data/ integrated intensity data" in Fullprof but it is giving error...

30 January 2021 7,813 3 View

How to take into account the high resolution of the x-ray difractometer?

At small angles or in case high collimation, the peaks become anisotropic and with a Lorentz addition. The resolution describes correctly only with adding Lorentz and anisatropy parameters. It...

26 January 2021 5,829 4 View

Can someone advise me to do Rietveld Refinement of the material whose Crystallographic Information Framework (CIF) file is not available?

10 October 2020 7,411 9 View

How to fix the refinement on Fullprof?

I have an XRD pattern of malachite phase in a range of 5-50 degree in 2 theta. After that, I use MID-JADE software to refine the pattern and it shows a good refinement with low R-value and GOF...

03 October 2020 3,613 8 View

How is it possible to simulate or model particle morphology using X-ray powder diffraction?

Hello everyone! I suppose the XRD of sample LaPO4 has some anisotropic line broadening along [h00]. How could I model the shape of particle using WPPF method or something else? Diffraction...

21 September 2020 1,823 3 View

Can someone help me with a standard Silicon Rietveld Refinement in GSAS II?

15 September 2020 3,085 7 View

What's the acceptable value of _refine_ls_shift/su_max for Rietveld refinement?

Hi, my background is in single-crystal X-ray diffraction. Now, I am carrying out the so-called Rietveld refinements in GSAS-II and am getting quite large _refine_ls_shift/su_max values (ranging...

01 September 2020 7,012 2 View