diff --git a/src/MISC/fix_ttm.cpp b/src/MISC/fix_ttm.cpp
index 757b2a619b..653797ba43 100644
--- a/src/MISC/fix_ttm.cpp
+++ b/src/MISC/fix_ttm.cpp
@@ -42,11 +42,11 @@ using namespace FixConst;
 
 FixTTM::FixTTM(LAMMPS *lmp, int narg, char **arg) :
   Fix(lmp, narg, arg),
-  random(NULL), fp(NULL), nsum(NULL), nsum_all(NULL),
-  T_initial_set(NULL), gfactor1(NULL), gfactor2(NULL), ratio(NULL),
-  flangevin(NULL), T_electron(NULL), T_electron_old(NULL), sum_vsq(NULL),
-  sum_mass_vsq(NULL), sum_vsq_all(NULL), sum_mass_vsq_all(NULL),
-  net_energy_transfer(NULL), net_energy_transfer_all(NULL)
+  random(NULL), fp(NULL), T_initial_set(NULL), nsum(NULL), nsum_all(NULL),
+  gfactor1(NULL), gfactor2(NULL), ratio(NULL), flangevin(NULL),
+  T_electron(NULL), T_electron_old(NULL), sum_vsq(NULL), sum_mass_vsq(NULL),
+  sum_vsq_all(NULL), sum_mass_vsq_all(NULL), net_energy_transfer(NULL),
+  net_energy_transfer_all(NULL)
 {
   if (narg < 15) error->all(FLERR,"Illegal fix ttm command");
 
@@ -327,7 +327,7 @@ void FixTTM::reset_dt()
 
 void FixTTM::read_initial_electron_temperatures(const char *filename)
 {
-  memset(&T_initial_set[0][0][0],0,total_nnodes*sizeof(double));
+  memset(&T_initial_set[0][0][0],0,total_nnodes*sizeof(int));
 
   std::string name = utils::get_potential_file_path(filename);
   if (name.empty())
@@ -360,8 +360,9 @@ void FixTTM::read_initial_electron_temperatures(const char *filename)
       error->one(FLERR,"Fix ttm electron temperatures must be > 0.0");
 
     T_electron[ixnode][iynode][iznode] = T_tmp;
-    T_initial_set[ixnode][iynode][iznode] = 1.0;
+    T_initial_set[ixnode][iynode][iznode] = 1;
   }
+  fclose(fpr);
 
   // check completeness of input data
 
@@ -370,8 +371,6 @@ void FixTTM::read_initial_electron_temperatures(const char *filename)
       for (int iznode = 0; iznode < nznodes; iznode++)
         if (T_initial_set[ixnode][iynode][iznode] == 0)
           error->one(FLERR,"Initial temperatures not all set in fix ttm");
-
-  fclose(fpr);
 }
 
 /* ---------------------------------------------------------------------- */
diff --git a/src/MISC/fix_ttm.h b/src/MISC/fix_ttm.h
index de8554e84f..722fada588 100644
--- a/src/MISC/fix_ttm.h
+++ b/src/MISC/fix_ttm.h
@@ -55,10 +55,9 @@ class FixTTM : public Fix {
   FILE *fp;
   int nxnodes,nynodes,nznodes;
   bigint total_nnodes;
-  int ***nsum;
-  int ***nsum_all,***T_initial_set;
-  double *gfactor1,*gfactor2,*ratio;
-  double **flangevin;
+  int ***T_initial_set;
+  int ***nsum, ***nsum_all;
+  double *gfactor1,*gfactor2,*ratio,**flangevin;
   double ***T_electron,***T_electron_old;
   double ***sum_vsq,***sum_mass_vsq;
   double ***sum_vsq_all,***sum_mass_vsq_all;
diff --git a/src/USER-MISC/fix_ttm_mod.cpp b/src/USER-MISC/fix_ttm_mod.cpp
index 15911ea6e5..4e23cb10df 100644
--- a/src/USER-MISC/fix_ttm_mod.cpp
+++ b/src/USER-MISC/fix_ttm_mod.cpp
@@ -66,7 +66,12 @@ static const char cite_fix_ttm_mod[] =
 /* ---------------------------------------------------------------------- */
 
 FixTTMMod::FixTTMMod(LAMMPS *lmp, int narg, char **arg) :
-  Fix(lmp, narg, arg), fp(NULL)
+  Fix(lmp, narg, arg),
+  random(NULL), fp(NULL), T_initial_set(NULL), nsum(NULL), nsum_all(NULL),
+  gfactor1(NULL), gfactor2(NULL), ratio(NULL), flangevin(NULL),
+  T_electron(NULL), T_electron_old(NULL), sum_vsq(NULL), sum_mass_vsq(NULL),
+  sum_vsq_all(NULL), sum_mass_vsq_all(NULL), net_energy_transfer(NULL),
+  net_energy_transfer_all(NULL)
 {
   if (lmp->citeme) lmp->citeme->add(cite_fix_ttm_mod);
 
@@ -521,7 +526,7 @@ void FixTTMMod::read_parameters(const char *filename)
 
 void FixTTMMod::read_initial_electron_temperatures(const char *filename)
 {
-  memset(&T_initial_set[0][0][0],0,total_nnodes*sizeof(double));
+  memset(&T_initial_set[0][0][0],0,total_nnodes*sizeof(int));
 
   std::string name = utils::get_potential_file_path(filename);
   if (name.empty())
@@ -557,6 +562,14 @@ void FixTTMMod::read_initial_electron_temperatures(const char *filename)
     T_initial_set[ixnode][iynode][iznode] = 1;
   }
   fclose(fpr);
+
+  // check completeness of input data
+
+  for (int ixnode = 0; ixnode < nxnodes; ixnode++)
+    for (int iynode = 0; iynode < nynodes; iynode++)
+      for (int iznode = 0; iznode < nznodes; iznode++)
+        if (T_initial_set[ixnode][iynode][iznode] == 0)
+          error->one(FLERR,"Initial temperatures not all set in fix ttm");
 }
 
 /* ---------------------------------------------------------------------- */
diff --git a/src/USER-MISC/fix_ttm_mod.h b/src/USER-MISC/fix_ttm_mod.h
index f51b79322c..30a3a8fdcf 100644
--- a/src/USER-MISC/fix_ttm_mod.h
+++ b/src/USER-MISC/fix_ttm_mod.h
@@ -58,11 +58,11 @@ class FixTTMMod : public Fix {
   int seed;
   class RanMars *random;
   FILE *fp;
-  int nxnodes,nynodes,nznodes,total_nnodes;
-  int ***nsum;
-  int ***nsum_all,***T_initial_set;
-  double *gfactor1,*gfactor2,*ratio;
-  double **flangevin;
+  int nxnodes,nynodes,nznodes;
+  bigint total_nnodes;
+  int ***T_initial_set;
+  int ***nsum, ***nsum_all;
+  double *gfactor1,*gfactor2,*ratio,**flangevin;
   double ***T_electron,***T_electron_old,***T_electron_first;
   double ***sum_vsq,***sum_mass_vsq;
   double ***sum_vsq_all,***sum_mass_vsq_all;