Cell parameters: Difference between revisions

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   Table shows the calculated (Calc.) and experimental (Exp.) values in amstrongs and the error between them in percentage.  
   Table shows the calculated (Calc.) and experimental (Exp.) values in amstrongs and the error between them in percentage.  


                  Calc.     Exp.  Error
                  Calc.   Exp.  Error
                                                      
                                                      
         Ag      4.227  4.0853    3     
         Ag      4.227  4.0853    3     

Revision as of 17:26, 30 January 2008

Calculations have been performed for Ag, Au, Cu, Ir, Pd, Pt and Rh in faced-centered cubic (fcc) structure, the most stable for all of them. Metal bulk have been calculated performing a Brillouin-zone integration with grids of 11x11x11 Monkhorst-Pack k-points. In order to optimize the cell parameter a, a scan around the expected value (for example the experimental one) is performed. That is, we select a set of values close to the experimental one, and calculate the energy for each one. Then we fit a third degree polynomial function with the energy versus the selected values as variables, and locate the minimum. This is the selected value.

 Table shows the calculated (Calc.) and experimental (Exp.) values in amstrongs and the error between them in percentage. 
                  Calc.    Exp.   Error
                                                    
        Ag       4.227   4.0853    3    
        Au       4.208   4.0782    3      
        Cu       3.676   3.6149    2     
        Ir       3.879   3.839     1     
        Pd       3.987   3.8907    2    
        Pt       3.990   3.9242    2      
        Rh       3.856   3.8034    1