Differences

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--- potfiles:main [2018/09/22 14:29] – daniel
+++ potfiles:main [2018/09/24 17:29] (current) – daniel
@@ Line 6: / Line 6: @@
 Each potential file consists of a header and a body, just like the configurations. While the header format is the same for all supported potentials the body format is fundamentally different for tabulated, analytic and KIM potentials.
-For potentials implemented in //potfit// the number of potentials and parameters required for each interaction is given on the bottom of each interaction page. For KIM potentials please see the [[potfiles:format4|KIM format]] page for details.
+For potentials implemented in //potfit// the number of potentials and parameters required for each interaction is given on the bottom of each interaction page. For KIM potentials please see the [[potfiles:format5|KIM format]] page for details.
 ====  Potential File Header  ====
@@ Line 48: / Line 48: @@
 == #C ==
-The line ''#C'' specifies the chemical elements the potentials belong to. Currently this line is not
+The optional line ''#C'' specifies the chemical elements the potentials belong to. This needs to match the
-read for potentials, it is only given in the output to facilitate the handling of potential files. In
+order of chemical elements in the configuration file. In output files //potfit// will write a comment on how the potentials are ordered. For the ternary system AlPdMn this looks like this:
-addition there will also be a comment on how the potentials are ordered, for the ternary system AlPdMn
-a header for an EAM-potential could look like the following:
 <code potfit>
-#F 0 12
 #C Al Pd Mn
 ## Al-Al Al-Pd Al-Mn Pd-Pd Pd-Mn Mn-Mn Al Pd Mn Al Pd Mn
-#I 0 0 0 0 0 0 0 0 0 0 0 0
-#E
 </code>
 == #I ==
-The line ''#I'' defines whether a whole potential function should be kept constant during a force
+The optional line ''#I'' defines whether a whole potential function should be kept constant during a force
-matching run. Each digit corresponds to one function table, so there should be n digits in total. A
+matching run. Each argument corresponds to one function, so there need to be as much digits as there are potential functions. A value of ''0'' allows //potfit// to change the corresponding potential function, a value of ''1'' keeps it fixed. This is useful for example if a third component is to be added to a binary system
-value of ''0'' allows //potfit// to change the corresponding potential function, a value of ''1''
+and only the additional potentials are to be allowed to change. If this line is omitted all potential functions will be optimized.
-keeps it fixed. This is useful for example if a third component is to be added to a binary system
-and only the additional potentials are to be allowed to change.
 == #G ==
-The line ''#G'' specifies whether the gradient of the interpolation splines should be treated as fixed
+The optional line ''#G'' specifies whether the gradient of the interpolation splines should be treated as fixed
-or as an additional degree of freedom. Each digit corresponds to one function table, so there should be
+or as an additional degree of freedom. Each argument corresponds to one potential function, so there should be
-n digits in total. The information is bit-coded, ''0'' declares both lower and upper gradient fixed,
+n arguments in total. The information is bit-coded, ''0'' declares both lower and upper gradient fixed,
 ''1'' allows adjusting the gradient at the upper end, ''2'' at the lower end, and ''3'' at both ends.
 This does not apply to analytic potentials.
@@ Line 79: / Line 72: @@
 == #E ==
-The very last header line must have
+The last line of the header must have the ''#E'' specifier, which indicates the end of the header part.
-a character ''E'' at the second position.
 ----