Hello!

I am working in getting my first run setup in RMCProfile7 and am building my .dat file. I am particularly interested in modeling solvation (liquid) structure of various systems and am working to setup a basic use case. My plan is to fit G® 'G®_PDFGui' of liquid DMSO. My starting configuration is a structure file taken from a frozen DMSO unit cell to act as an ordered initial condition. My thought is that I could constrain the translation and rotations of the rigid DMSO molecules to fit the amorphous liquid structure.

Here is my current setup of the MOLECULE :: subsection of the .dat file:

%%%%%%%%
MOLECULE ::
  > ATOM :: O
  > ATOM :: S 1 1.3 1.6 Angstrom
  > ATOM :: C 2 1.7 1.9 Angstrom
  > ATOM :: C 2 1.7 1.9 Angstrom
  > MAXIMUM_MOVES :: 3 3 3 3    %% Not sure how to setup this condition
  > MOVE_PROBABILITIES :: 0.5
  > ROTATION_PROBABILITIES :: 0.5
  > MOLECULE_FILE :: dmso.list     %% Not sure how to format this file?
%%  > MINIMUM_ROTATION :: 0 0 0
%%  > MAXIMUM_ROTATION :: 180 180 180 
%%%%%%%%

- What is the format of the MOLECULE_FILE? Is there an example of this file format somewhere and a tool to help generate this?
Reading molecule list data file: 'dmso.list
Error  >  No atoms collections found in molecule list file!

- How should I setup the MAXIMUM_MOVES, MINIMUM_ROTATION, AND MAXIMUM_ROTATION? I am getting keyword errors for the rotation inputs:
Warning>  Unrecognised keyword: 'MINIMUM_ROTATION'Warning>  Value of unrecognised keyword: '0 0 0'
Warning>  Line number of unrecognised keyword: 28
Warning>  Unrecognised keyword: 'MAXIMUM_ROTATION'
Warning>  Value of unrecognised keyword: '180 180 180'

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RMCProfile version 7b.200
Operating System: macOS Monterey v. 12.0.1
Chip: Apple M1 Max

We have collected information about those working items happening at ORNL concerning the software development for powder diffraction data processing and analysis. This includes those items that we collaboratively work with the software support team and those worked on independently by teams/personnel at ORNL.

Here you can find the collection of information, Click Me.

Please feel free to put down your comments concerning those active working items, or put down whatever you think is missing in the list that we should work on.

https://addie.ornl.gov/conf_viewer

Hi, all,

"NEUTRON_COEFFICIENTS" is explicitly used as a subordinate keyword for "NEUTRON_REAL_SPACE_DATA" and "NEUTRON_RECIPROCAL_SPACE_DATA",

So, what about "XRAY_RECIPROCAL_SPACE_DATA",
          
         (1) The subordinate keywords under the main keyword are directly entered as "NEUTRON_COEFFICIENTS";

   

For those who are interested in using Topas Bragg profile data in RMCProfile fitting, please refer to our post here for details.

Hi all.

I would like to fit anomalous X-ray scattering (AXS) and neutron data for a crystalline sample with partial occupancies. Are there any plans to add the function to analyze AXS data? Or do you have any alternative idea to do it?
(I know that RMC++ can analyze AXS data but is not good at analyzing Bragg peaks.)

Thank you.

Yasu

Here in the following link, I put the test result of the running time for current data reduction routine used for powder diffraction data reduction,

https://powder.ornl.gov/run_time.html

It will be very nice if you can take a look at your instrument and give feedback in current thread.

You can just log in with your UCAMS to post.

To vote, put down your instrument name followed by your vote, like this ('+1' means it looks good, '-1' means you are expected shorter running time and so you need to give your expected running time),

N.B. I know that the actual running time really depends on the samples and data involved in the reduction. In the link above, I put down all the files I have been using for getting the running time result, so we can use them as the reference for the discussion and voting.

HB2A: +1
HB2A: -1, [My expected running time]

HB2C: +1
HB2C: -1, [My expected running time]

NOMAD: +1
NOMAD: -1, [My expected running time]

POWGEN: +1
POWGEN: -1, [My expected running time]

Experimental Planning Tools

Scattering in the cloud (temporary, but strongly recommended),

https://addie.ornl.gov

This web based tool contains the following capabilities,

• Structure mining: By providing a composition and a measured PDF, the engine can mine the database for best suitable structure
  
• PDF or Bragg pattern simulation
  
• PDF or Bragg pattern refinement
  
• Total scattering help sheet
  

• Neutron scattering length,
  https://www.ncnr.nist.gov/resources/n-lengths/
  

• Neutron absorption calculation,
  https://www.ncnr.nist.gov/resources/acti...utron.html
  

• Neutron resonance absorption,
  https://www.ncnr.nist.gov/resources/acti...nance.html