diff --git a/src/Init/DiffusionInit.cpp b/src/Init/DiffusionInit.cpp
index becaaa977..c740091a5 100644
--- a/src/Init/DiffusionInit.cpp
+++ b/src/Init/DiffusionInit.cpp
@@ -146,9 +146,12 @@ static Rcpp::List parseAlphas2D(const SEXP &input,
   return out_list;
 }
 void InitialList::initDiffusion(const Rcpp::List &diffusion_input) {
-  const Rcpp::List &boundaries = diffusion_input["boundaries"];
-  const SEXP &alpha_x = diffusion_input["alpha_x"];
-  const SEXP &alpha_y = diffusion_input["alpha_y"];
+  const Rcpp::List &boundaries =
+      diffusion_input[DIFFU_MEMBER_STR(DiffusionMembers::BOUNDARIES)];
+  const Rcpp::NumericVector &alpha_x =
+      diffusion_input[DIFFU_MEMBER_STR(DiffusionMembers::ALPHA_X)];
+  const Rcpp::NumericVector &alpha_y =
+      diffusion_input[DIFFU_MEMBER_STR(DiffusionMembers::ALPHA_Y)];
 
   std::vector<std::string> colnames =
       Rcpp::as<std::vector<std::string>>(this->initial_grid.names());
diff --git a/src/Init/GridInit.cpp b/src/Init/GridInit.cpp
index eead62881..8e5061c76 100644
--- a/src/Init/GridInit.cpp
+++ b/src/Init/GridInit.cpp
@@ -100,29 +100,31 @@ void InitialList::initGrid(const Rcpp::List &grid_input) {
   std::string database;
 
   if (grid_input.containsElementNamed(
-          getGridMemberString(GridMembers::PQC_SCRIPT_FILE))) {
+          GRID_MEMBER_STR(GridMembers::PQC_SCRIPT_FILE))) {
 
     script = readFile(Rcpp::as<std::string>(
-        grid_input[getGridMemberString(GridMembers::PQC_SCRIPT_FILE)]));
+        grid_input[GRID_MEMBER_STR(GridMembers::PQC_SCRIPT_FILE)]));
   } else {
     script = Rcpp::as<std::string>(
-        grid_input[getGridMemberString(GridMembers::PQC_SCRIPT_STRING)]);
+        grid_input[GRID_MEMBER_STR(GridMembers::PQC_SCRIPT_STRING)]);
   }
 
   if (grid_input.containsElementNamed(
-          getGridMemberString(GridMembers::PQC_DB_FILE))) {
+          GRID_MEMBER_STR(GridMembers::PQC_DB_FILE))) {
 
     database = readFile(Rcpp::as<std::string>(
-        grid_input[getGridMemberString(GridMembers::PQC_DB_FILE)]));
+        grid_input[GRID_MEMBER_STR(GridMembers::PQC_DB_FILE)]));
   } else {
     database = Rcpp::as<std::string>(
-        grid_input[getGridMemberString(GridMembers::PQC_DB_STRING)]);
+        grid_input[GRID_MEMBER_STR(GridMembers::PQC_DB_STRING)]);
   }
 
+  this->database = database;
+
   Rcpp::NumericMatrix grid_def =
-      grid_input[getGridMemberString(GridMembers::GRID_DEF)];
+      grid_input[GRID_MEMBER_STR(GridMembers::GRID_DEF)];
   Rcpp::NumericVector grid_size =
-      grid_input[getGridMemberString(GridMembers::GRID_SIZE)];
+      grid_input[GRID_MEMBER_STR(GridMembers::GRID_SIZE)];
   // Rcpp::NumericVector constant_cells = grid["constant_cells"].;
 
   this->n_rows = grid_def.nrow();
@@ -155,6 +157,13 @@ void InitialList::initGrid(const Rcpp::List &grid_input) {
 
   this->module_sizes = getModuleSizes(phreeqc, this->initial_grid);
 
+  std::vector<std::string> colnames =
+      Rcpp::as<std::vector<std::string>>(this->initial_grid.names());
+
+  this->to_transport = this->pqc_sol_order = std::vector<std::string>(
+      colnames.begin() + 1,
+      colnames.begin() + 1 + this->module_sizes[POET_SOL]);
+
   // print module sizes
   for (std::size_t i = 0; i < this->module_sizes.size(); i++) {
     std::cout << this->module_sizes[i] << std::endl;
diff --git a/src/Init/InitialList.hpp b/src/Init/InitialList.hpp
index b75a9b2d8..bc4a4dafd 100644
--- a/src/Init/InitialList.hpp
+++ b/src/Init/InitialList.hpp
@@ -51,7 +51,7 @@ private:
                            "pqc_db_file",    "grid_def",    "grid_size",
                            "constant_cells", "porosity"};
 
-  constexpr const char *getGridMemberString(GridMembers member) const {
+  constexpr const char *GRID_MEMBER_STR(GridMembers member) const {
     return GridMembersString[static_cast<std::size_t>(member)];
   }
 
@@ -71,20 +71,44 @@ private:
   // No export
   Rcpp::NumericMatrix phreeqc_mat;
 
-  // Initialized by grid, modified by chemistry
+  // Initialized by grid
   std::map<int, std::string> pqc_raw_dumps;
 
   // Chemistry members
   IPhreeqcPOET::ModulesArray module_sizes;
 
   // Diffusion members
-
   static constexpr const char *diffusion_key = "Diffusion";
 
+  enum class DiffusionMembers { BOUNDARIES, ALPHA_X, ALPHA_Y, ENUM_SIZE };
+
+  static constexpr std::size_t size_DiffusionMembers =
+      static_cast<std::size_t>(InitialList::DiffusionMembers::ENUM_SIZE);
+
+  static constexpr std::array<const char *, size_DiffusionMembers>
+      DiffusionMembersString = {"boundaries", "alpha_x", "alpha_y"};
+
+  constexpr const char *DIFFU_MEMBER_STR(DiffusionMembers member) const {
+    return DiffusionMembersString[static_cast<std::size_t>(member)];
+  }
+
   void initDiffusion(const Rcpp::List &diffusion_input);
   Rcpp::List boundaries;
 
   Rcpp::List alpha_x;
   Rcpp::List alpha_y;
+
+  std::vector<std::string> to_transport;
+
+  // Chemistry Members
+  static constexpr const char *chemistry_key = "Chemistry";
+
+  void initChemistry();
+
+  std::string database;
+  std::vector<std::string> pqc_scripts;
+  std::vector<int> pqc_ids;
+
+  std::vector<std::string> pqc_sol_order;
 };
 } // namespace poet
\ No newline at end of file