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potfiles:format0 [2018/09/23 18:23] danielpotfiles:format0 [2021/03/29 21:08] (current) daniel
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 ~~NOTOC~~ ~~NOTOC~~
 ======  Potential File Format 0  ====== ======  Potential File Format 0  ======
 +
 ----- -----
 +
 +===== Format specification =====
  
 The potential format ''0'' is used for analytical potentials exclusively.  The potential format ''0'' is used for analytical potentials exclusively. 
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 === type === === type ===
  
-The ''type'' keyword has to be followed by the [[:analytic_functions|unique identifier]] for +The ''type'' keyword has to be followed by the [[models:analytic_functions|unique identifier]] for 
 the analytic function. To enable the smooth cutoff option ''_sc'' can be added at the end of the identifer (this also adds another parameter to the end potential function!). the analytic function. To enable the smooth cutoff option ''_sc'' can be added at the end of the identifer (this also adds another parameter to the end potential function!).
  
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 # Lennard-Jones with smooth cutoff option enabled # Lennard-Jones with smooth cutoff option enabled
-type morse_sc+type lj_sc
 epsilon 1 0 2 epsilon 1 0 2
 sigma 1 0 2 sigma 1 0 2
 h 1 0 2 h 1 0 2
 </code>  </code> 
 +
 +All list of all supported analytic potential functions is available [[models:analytic_functions|here]].
  
 === cutoff === === cutoff ===
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 with an identifier for that parameter followed by the starting value, the minimum and maximum value for  with an identifier for that parameter followed by the starting value, the minimum and maximum value for 
 that parameter. The order of these parameters is fixed, for the implemented analytic functions the order  that parameter. The order of these parameters is fixed, for the implemented analytic functions the order 
-can be found [[:analytic_functions|here]]. +can be found [[models:analytic_functions|here]].
- +
------ +
- +
-=== Example === +
- +
-<code potfit format_0_example.txt> +
-#F 0 1 +
-#C Al +
-## Al-Al +
-#E +
- +
-type lj_sc +
-cutoff 7.000000 +
-# rmin 2.159655 +
-epsilon 2100.0633799282 0.500000 10000.000000 +
-sigma 10.3066290006 1.000000 20.000000 +
-h 1 0.5 2 +
-</code> +
- +
-A sample format 0 potential file for a binary EAM potential is available {{:format_0.pot.txt|here}}. +
  
 +Giving three times the same value will remove this parameter from the optimization table and use exactly that value when calculating forces/energies. This is usually called a fixed parameter.
  
-~~NOTOC~~ 
-====== Analytic potentials ====== 
 ---- ----
  
-Analytic potentials can be enabled in //potfit// by compiling it with the ''apot'' switch.  +===== Additional features =====
-There are some additional options for analytic potentials like the chemical potentials or the smooth cutoff.+
  
 ====  Global parameters  ==== ====  Global parameters  ====
  
 //potfit// supports global parameters, which can occur in different potentials. With this feature it is possible for any potential to "share" parameters with each other.  //potfit// supports global parameters, which can occur in different potentials. With this feature it is possible for any potential to "share" parameters with each other. 
-To use them, you need a section called ''global n'' after the header in your potential file, where ''n'' is the number of global parameters. +To use them, you need a section starting with ''global <n>'' after the header in your potential file, where ''n'' is the number of global parameters. 
 The format for the parameters is the same as for normal parameters: ''name value min max''. The format for the parameters is the same as for normal parameters: ''name value min max''.
 If you want to use a global parameter in a potential, use the name of the global parameter and add an exclamation mark. If you want to use a global parameter in a potential, use the name of the global parameter and add an exclamation mark.
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 If you omit it, it will be kept fixed at a value of 1. If you omit it, it will be kept fixed at a value of 1.
  
-====  Implemented Potential Functions  ====+----
  
-The currently implemented analytic potential functions can be found [[:analytic_functions|here]].+===== Examples =====
  
-====  Adding New Potential Functions  ====+<code potfit format_0_example.txt> 
 +#F 0 1 
 +#C Al 
 +## Al-Al 
 +#E 
 + 
 +type lj_sc 
 +cutoff 7.000000 
 +# rmin 2.159655 
 +epsilon 2100.0633799282 0.500000 10000.000000 
 +sigma 10.3066290006 1.000000 20.000000 
 +h 1 0.5 2 
 +</code>
  
-If you want to add other analytic potentials see [[:add_new_functions|this guide]].+Many more examples are available in the [[examples:potentials|potential examples]] section.
  
potfiles/format0.1537719783.txt.gz · Last modified: 2018/09/23 18:23 by daniel