From 92515dc9ab5faf50308eb94381a9c943e6061305 Mon Sep 17 00:00:00 2001
From: Ian Bell <ian.bell@nist.gov>
Date: Thu, 7 Sep 2023 12:06:34 -0400
Subject: [PATCH] Another error is needed

---
 include/teqp/models/saft/polar_terms.hpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/teqp/models/saft/polar_terms.hpp b/include/teqp/models/saft/polar_terms.hpp
index 237fc6df..a018d36a 100644
--- a/include/teqp/models/saft/polar_terms.hpp
+++ b/include/teqp/models/saft/polar_terms.hpp
@@ -934,6 +934,9 @@ class MultipolarContributionGrayGubbins {
             // The packing fraction is defined by eta = pi/6*rho^*, so use the (temperature-dependent) eta to obtain rho^*
             rhostar = forceeval(packing_fraction/(static_cast<double>(EIGEN_PI)/6.0));
         }
+        else{
+            throw teqp::InvalidArgument("The method used to determine rho^* is invalid");
+        }
         return rhostar;
     }