[cig-commits] [commit] add_thermodynamic_potentials: Emphasised the physical meaning of the normalisation constant in activity calculations (e692ab9)

[cig_noreply at geodynamics.org]

Repository : https://github.com/geodynamics/burnman

On branch  : add_thermodynamic_potentials
Link       : https://github.com/geodynamics/burnman/compare/2e5646d93cedbbf8eae54cc37cffc14e0aa85180...d5ddad03ff9f30f5a4efaddb4e3ec585ea1a7c51

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commit e692ab9b2de72223277a680666d93c2cffec2bf2
Author: Bob Myhill <myhill.bob at gmail.com>
Date:   Fri Sep 5 01:38:19 2014 +0200

    Emphasised the physical meaning of the normalisation constant in activity calculations


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e692ab9b2de72223277a680666d93c2cffec2bf2
 burnman/solutionmodel.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/burnman/solutionmodel.py b/burnman/solutionmodel.py
index 56549b6..f8d39f8 100644
--- a/burnman/solutionmodel.py
+++ b/burnman/solutionmodel.py
@@ -125,11 +125,10 @@ class IdealSolution ( SolutionModel ):
 
         for e in range(self.n_endmembers):
             activities[e]=1.0
-            normalisation_constant=1.0
             for occ in range(self.n_occupancies):
                 if self.endmember_occupancies[e][occ] > 1e-10:
                     activities[e]=activities[e]*np.power(site_occupancies[occ],self.endmember_occupancies[e][occ]*self.site_multiplicities[occ])
-                    normalisation_constant=normalisation_constant/np.power(self.endmember_occupancies[e][occ],self.endmember_occupancies[e][occ]*self.site_multiplicities[occ])
+            normalisation_constant=np.exp(self.endmember_configurational_entropies[e]/R)
             activities[e]=normalisation_constant*activities[e]
         return activities