X ray diffraction and GsAs -II software

Create a GSAS-II project that begins with your last name. (e.g., Meesala_znnbo_v00) 2. Load the CIF and data, use the ‘Default CuKalpha’ instrument parameter file. For the following steps, provide a summary of your approach to each. Do not refine the instrument parameter files, but you may refine sample displacement. 3. Using any approach you like, fit the background of the data. 4. Refine appropriate parameters to capture peak positions at low and high angles. Remember that sometimes running the same refinement conditions multiple times can continue to improve the fit. Describe 2 approaches to continue to improve the fit, especially by refining things in the “Data”, “Atoms”, and both together. *At least one approach should improve the fit and have physically meaningful values for all relevant parameters. Continue to summarize what you refine and how it goes. In addition, make sure that any refined values are physical, especially LGmix and thermal displacement parameters (i.e., Uiso), or describe if these repeatedly become non-physical. (Note: O atom Uiso and position should not be refined with lab X-ray data, such as this.) 5. Approach 1: a. State of fit before (image and wR value): b. Parameter(s) refined: c. State of fit after (image and wR value): d. Reflection and check of refined parameter values: 6. Approach 2: a. State of fit before (image and wR value): b. Parameter(s) refined: c. State of fit after (image and wR value): d. Reflection and check of refined parameter values: 7. Results: a. Compare the lattice parameters and any microstructure information for your original vs. refined models. Is the model significantly different? Explain in 2-4 sentences.