FLiNaK is a widely studied fluoride salt for nuclear applications. For practical purposes, this salt would be considered as a heat-exchange medium rather than a fuel carrier. However, we chose FLiNaK as a model because it is well studied, contains only simple single-valence ions, and does not contain toxic Be, like the leading fuel salt candidate FLiBe (LiF-BeF 2 eutectic). FLiNaK is similar in many respects to FLiBe (melting temperatures, density, thermal conductivity), but without the di culty of working with Be.