[cig-commits] [commit] add_gibbs_energy: Emphasised the physical meaning of the normalisation constant in activity calculations (43ef3b9)

[cig_noreply at geodynamics.org]

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

On branch  : add_gibbs_energy
Link       : https://github.com/geodynamics/burnman/compare/0000000000000000000000000000000000000000...2148b324d3e8aa7b527f831eb397590942563008

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commit 43ef3b9f00af3f22860a059fbc21a1089780f8ab
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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43ef3b9f00af3f22860a059fbc21a1089780f8ab
 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