I found below list when looking for vapor pressure data. Does it tell something ?

lgP (YF3) = 1,7259 + 1,1103.lgP(CaF2);
lgP (ScF3) = 2,2163 + 0,9641.lgP(CaF2);
lgP (PrF3) = 0,8570 + 0,9577.lgP(CaF2);
lgP (LaBr3) = 1,6662 + 0,5617.lgP(CaF2);
lgP (CeBr3) = 1,6852 + 0,5381.lgP(CaF2);
lgP (PrBr3) = 1,6978 + 0,5273.lgP(CaF2);
lgP (NdBr3) = 1,8257 + 0,5275.lgP(CaF2);
lgP (YBr3) = 2,2958 + 0,5003.lgP(CaF2);
lgP (HoBr3) = 2,1859 + 0,5017.lgP(CaF2);
lgP (LuBr3) = 2,4073 + 0,4691.lgP(CaF2);
lgP (TbBr3) = 1,9795 + 0,4946.lgP(CaF2);
lgP (GdBr3) = 1,9423 + 0,5057.lgP(CaF2).