diff --git a/Cantera/src/equil/vcs_Gibbs.cpp b/Cantera/src/equil/vcs_Gibbs.cpp
index 3b0b00b52..5fa7ea891 100644
--- a/Cantera/src/equil/vcs_Gibbs.cpp
+++ b/Cantera/src/equil/vcs_Gibbs.cpp
@@ -45,11 +45,7 @@ namespace VCSnonideal {
 	g += TPhInertMoles[iph] *
 	  log(TPhInertMoles[iph] / tPhMoles[iph]);
 	if (Vphase->GasPhase) {
-	  if (m_VCS_UnitsFormat == 3) {
-	    g += TPhInertMoles[iph] * log(m_pressure/(Cantera::OneAtm));
-	  } else {
-	    g += TPhInertMoles[iph] * log(m_pressure);
-	  }
+	  g += TPhInertMoles[iph] * log(m_pressurePA/(1.01325E5));
 	}
       }
     }
@@ -86,11 +82,7 @@ namespace VCSnonideal {
       g += TPhInertMoles[iphase] * log(TPhInertMoles[iphase] / phaseMols);
       vcs_VolPhase *Vphase = VPhaseList[iphase];
       if (Vphase->GasPhase == iphase) {
-	if (m_VCS_UnitsFormat == 3) {
-	  g += TPhInertMoles[iphase] * log(m_pressure/(Cantera::OneAtm));
-	} else {
-	  g += TPhInertMoles[iphase] * log(m_pressure);
-	}
+	g += TPhInertMoles[iphase] * log(m_pressurePA/1.01325E5);
       }
     }
 
diff --git a/Cantera/src/equil/vcs_MultiPhaseEquil.cpp b/Cantera/src/equil/vcs_MultiPhaseEquil.cpp
index c1bbd7967..7a4cedad4 100644
--- a/Cantera/src/equil/vcs_MultiPhaseEquil.cpp
+++ b/Cantera/src/equil/vcs_MultiPhaseEquil.cpp
@@ -668,12 +668,7 @@ namespace VCSnonideal {
      }
      plogf("\n");
      plogf("Temperature = %g Kelvin\n",  m_vprob->T);
-     plogf("Pressure    = %g ", m_vprob->Pres);
-     if (m_vprob->m_VCS_UnitsFormat == VCS_UNITS_MKS) {
-       plogf("Pa\n");
-     } else  {
-       plogf("atm\n");
-     }
+     plogf("Pressure    = %g Pa\n", m_vprob->PresPA);
      plogf("\n");
      plogf("----------------------------------------"
 	    "---------------------\n");
@@ -1099,7 +1094,7 @@ namespace VCSnonideal {
     // We will work out the details later.
     vprob->iest      = -1;
     vprob->T         = mphase->temperature();
-    vprob->Pres      = mphase->pressure();
+    vprob->PresPA    = mphase->pressure();
     vprob->Vol       = mphase->volume();
     vprob->Title     = "MultiPhase Object";
 
@@ -1225,7 +1220,7 @@ namespace VCSnonideal {
        */
       vprob->addPhaseElements(VolPhase);
 
-      VolPhase->setState_TP(vprob->T, vprob->Pres);
+      VolPhase->setState_TP(vprob->T, vprob->PresPA);
       vector<double> muPhase(tPhase->nSpecies(),0.0);
       tPhase->getChemPotentials(&muPhase[0]);
       double tMoles = 0.0;
@@ -1426,14 +1421,14 @@ namespace VCSnonideal {
       print_char('=', 80); plogf("\n");
       plogf("             Phase IDs of species\n");
       plogf("            species     phaseID        phaseName   ");
-      plogf(" Initial_Estimated_gMols\n");
+      plogf(" Initial_Estimated_kMols\n");
       for (int i = 0; i < vprob->nspecies; i++) {
 	int iphase = vprob->PhaseID[i];
 
 	vcs_VolPhase *VolPhase = vprob->VPhaseList[iphase];
 	plogf("%16s      %5d   %16s", vprob->SpName[i].c_str(), iphase,
 	       VolPhase->PhaseName.c_str());
-	plogf("             %-10.5g\n",  1.0E3 * vprob->w[i]);
+	plogf("             %-10.5g\n",  vprob->w[i]);
       }
       
       /*
@@ -1442,7 +1437,7 @@ namespace VCSnonideal {
       plogf("\n"); print_char('-', 80); plogf("\n");
       plogf("             Information about phases\n");
       plogf("  PhaseName    PhaseNum SingSpec GasPhase EqnState NumSpec");
-      plogf("  TMolesInert       Tmoles(gmol)\n");
+      plogf("  TMolesInert       Tmoles(kmol)\n");
    
       for (int iphase = 0; iphase < vprob->NPhase; iphase++) {
 	vcs_VolPhase *VolPhase = vprob->VPhaseList[iphase];
@@ -1450,8 +1445,8 @@ namespace VCSnonideal {
 	plogf("%16s %5d %5d %8d %16s %8d %16e ", VolPhase->PhaseName.c_str(),
 	       VolPhase->VP_ID,       VolPhase->SingleSpecies,
 	       VolPhase->GasPhase,    sEOS.c_str(),
-	       VolPhase->NVolSpecies, VolPhase->TMolesInert * 1.0E3);
-	plogf("%16e\n",  VolPhase->TotalMoles() * 1.0E3);
+	       VolPhase->NVolSpecies, VolPhase->TMolesInert );
+	plogf("%16e\n",  VolPhase->TotalMoles());
       }
    
       plogf("\n"); print_char('=', 80); plogf("\n");
@@ -1479,7 +1474,7 @@ namespace VCSnonideal {
     // the call to the equilibrium solver.
     vprob->iest      = -1;
     vprob->T         = mphase->temperature();
-    vprob->Pres      = mphase->pressure();
+    vprob->PresPA    = mphase->pressure();
     vprob->Vol       = mphase->volume();
     Cantera::ThermoPhase *tPhase = 0;
 
@@ -1492,7 +1487,7 @@ namespace VCSnonideal {
        */
       volPhase->setElectricPotential(tPhase->electricPotential());
 
-      volPhase->setState_TP(vprob->T, vprob->Pres);
+      volPhase->setState_TP(vprob->T, vprob->PresPA);
       vector<double> muPhase(tPhase->nSpecies(),0.0);
       tPhase->getChemPotentials(&muPhase[0]);
       /*
@@ -1544,14 +1539,14 @@ namespace VCSnonideal {
       print_char('=', 80); plogf("\n\n");
       plogf("             Phase IDs of species\n");
       plogf("            species     phaseID        phaseName   ");
-      plogf(" Initial_Estimated_gMols\n");
+      plogf(" Initial_Estimated_kMols\n");
       for (int i = 0; i < vprob->nspecies; i++) {
 	int iphase = vprob->PhaseID[i];
 
 	vcs_VolPhase *VolPhase = vprob->VPhaseList[iphase];
 	plogf("%16s      %5d   %16s", vprob->SpName[i].c_str(), iphase,
 	       VolPhase->PhaseName.c_str());
-	plogf("             %-10.5g\n",  1.0E3 * vprob->w[i]);
+	plogf("             %-10.5g\n",  vprob->w[i]);
       }
       
       /*
@@ -1560,7 +1555,7 @@ namespace VCSnonideal {
       plogf("\n"); print_char('-', 80); plogf("\n");
       plogf("             Information about phases\n");
       plogf("  PhaseName    PhaseNum SingSpec GasPhase EqnState NumSpec");
-      plogf("  TMolesInert       Tmoles(gmol)\n");
+      plogf("  TMolesInert       Tmoles(kmol)\n");
    
       for (int iphase = 0; iphase < vprob->NPhase; iphase++) {
 	vcs_VolPhase *VolPhase = vprob->VPhaseList[iphase];
@@ -1568,8 +1563,8 @@ namespace VCSnonideal {
 	plogf("%16s %5d %5d %8d %16s %8d %16e ", VolPhase->PhaseName.c_str(),
 	       VolPhase->VP_ID,       VolPhase->SingleSpecies,
 	       VolPhase->GasPhase,    sEOS.c_str(),
-	       VolPhase->NVolSpecies, VolPhase->TMolesInert * 1.0E3);
-	plogf("%16e\n",  VolPhase->TotalMoles() * 1.0E3); 
+	       VolPhase->NVolSpecies, VolPhase->TMolesInert );
+	plogf("%16e\n",  VolPhase->TotalMoles() ); 
       }
    
       plogf("\n"); print_char('=', 80); plogf("\n");
diff --git a/Cantera/src/equil/vcs_TP.cpp b/Cantera/src/equil/vcs_TP.cpp
index 772a4f726..19c3df783 100644
--- a/Cantera/src/equil/vcs_TP.cpp
+++ b/Cantera/src/equil/vcs_TP.cpp
@@ -36,7 +36,7 @@ namespace VCSnonideal {
      *     ip1 = 1 -> Print intermediate results. 
      *     maxit -> Maximum number of iterations for the algorithm 
      *      T = Temperature (Kelvin)
-     *    pres = Pressure (units given by if__ variable)
+     *    pres = Pressure (pascal)
      *
      * Return Codes
      * ------------------
@@ -55,7 +55,7 @@ namespace VCSnonideal {
      *        Store the temperature and pressure in the private global variables
      */
     m_temperature = T_arg;
-    m_pressure = pres_arg;
+    m_pressurePA = pres_arg;
     /*
      *        Evaluate the standard state free energies
      *        at the current temperatures and pressures.
@@ -113,7 +113,7 @@ namespace VCSnonideal {
      *           0 -> don't report on anything 
      *     IP1 = 1 -> Print intermediate results. 
      *      T = Temperature (Kelvin)
-     *    Pres = Pressure (units of if__ variable)
+     *    Pres = Pressure (Pascal)
      *
      *    Evaluate the standard state free energies at the current temperature
      *    and pressure. Ideal gas pressure contribution is added in here.
@@ -154,7 +154,7 @@ namespace VCSnonideal {
 
     for (int iph = 0; iph < NPhase; iph++) {
       vcs_VolPhase* vph = VPhaseList[iph];
-      vph->setState_TP(m_temperature, m_pressure);
+      vph->setState_TP(m_temperature, m_pressurePA);
       vph->sendToVCSGStar(VCS_DATA_PTR(m_SSfeSpecies));
     }
    
diff --git a/Cantera/src/equil/vcs_VolPhase.cpp b/Cantera/src/equil/vcs_VolPhase.cpp
index 66463aca4..ca8ea2975 100644
--- a/Cantera/src/equil/vcs_VolPhase.cpp
+++ b/Cantera/src/equil/vcs_VolPhase.cpp
@@ -40,6 +40,7 @@ vcs_VolPhase::vcs_VolPhase() :
   ElGlobalIndex(0),
   NVolSpecies(0),
   TMolesInert(0.0),
+  m_molarVolInert(1000.),
   ActivityConvention(0),
   Existence(0),
   IndexSpecialSpecies(-1),
@@ -402,7 +403,7 @@ double vcs_VolPhase::G0_calc_one(int kspec, double tkelvin) {
  * The results are held internally within the object.
  *
  * @param TKelvin Current temperature
- * @param pres    Current pressure
+ * @param pres    Current pressure (pascal)
  */
 void vcs_VolPhase::GStar_calc(double tkelvin, double pres) {
   setState_TP(tkelvin, pres);
@@ -431,8 +432,8 @@ void vcs_VolPhase::GStar_calc(double tkelvin, double pres) {
  * The kth species standard state G is returned
  *
  * @param kspec   Species number (within the phase)
- * @param TKelvin Current temperature
- * @param pres    Current pressure
+ * @param TKelvin Current temperature (kelvin)
+ * @param pres    Current pressure (pascal)
  *
  * @return Gstar[kspec] returns the gibbs free energy for the
  *         standard state of the kth species.
@@ -694,7 +695,9 @@ void vcs_VolPhase::setState_TP(double temp, double pres)
  * The results are held internally within the object.
  *
  * @param TKelvin Current temperature
- * @param pres    Current pressure
+ * @param pres    Current pressure (pascal)
+ *
+ *  Calculations are in m**3/kmol
  */
 void vcs_VolPhase::VolStar_calc(double tkelvin, double pres) {
   setState_TP(tkelvin, pres);
@@ -722,7 +725,7 @@ void vcs_VolPhase::VolStar_calc(double tkelvin, double pres) {
  *
  * @param kspec Species number (within the phase)
  * @param TKelvin Current temperature
- * @param pres    Current pressure
+ * @param pres    Current pressure (pascal)
  *
  * @return molar volume of the kspec species's standard
  *         state
@@ -747,8 +750,7 @@ double vcs_VolPhase::VolPM_calc() const {
 	kglob = IndSpecies[k];
 	vcs_SpeciesProperties *sProp = ListSpeciesPtr[k];
 	VCS_SPECIES_THERMO *sTherm = sProp->SpeciesThermo;
-	StarMolarVol[k] =
-	  (sTherm->VolStar_calc(kglob, Temp, Pres));
+	StarMolarVol[k] = (sTherm->VolStar_calc(kglob, Temp, Pres));
       }
       for (k = 0; k < NVolSpecies; k++) {
 	PartialMolarVol[k] = StarMolarVol[k];
@@ -760,6 +762,16 @@ double vcs_VolPhase::VolPM_calc() const {
       Vol += PartialMolarVol[k] * Xmol[k];
     }
     Vol *= TMoles;
+
+    if (TMolesInert > 0.0) {
+      if (GasPhase) {
+	double volI = TMolesInert * 8314.47215 * Temp / Pres;
+	Vol += volI;
+      } else {
+	printf("unknown situation\n");
+	exit(-1);
+      }
+    }
   }
   m_UpToDate_VolPM = true;
   return Vol;
diff --git a/Cantera/src/equil/vcs_VolPhase.h b/Cantera/src/equil/vcs_VolPhase.h
index 19285ebff..e6f26ebbe 100644
--- a/Cantera/src/equil/vcs_VolPhase.h
+++ b/Cantera/src/equil/vcs_VolPhase.h
@@ -215,6 +215,12 @@ public:
   //!  Total moles of inert in the phase 
   double TMolesInert;
 
+  //! molar volume of the inert species if present
+  /*!
+   *  units m**3 / kg
+   */
+  double m_molarVolInert;
+
   //! Convention for the activity formulation
   /*!
    *  0 = molar based activities (default)
@@ -285,10 +291,10 @@ public:
    *
    *                           Chem_Pot                 Pres      vol   moles
    * ----------------------------------------------------------------------
-   * -1  VCS_UNITS_KCALMOL  = kcal/mol                  atm   cm**3   gmol
-   *  0  VCS_UNITS_UNITLESS = MU / RT -> no units       atm   cm**3   gmol
-   *  1  VCS_UNITS_KJMOL    = kJ / mol                  atm   cm**3   gmol
-   *  2  VCS_UNITS_KELVIN   = KELVIN -> MU / R          atm   cm**3   gmol
+   * -1  VCS_UNITS_KCALMOL  = kcal/gmol                 Pa     m**3   kmol
+   *  0  VCS_UNITS_UNITLESS = MU / RT -> no units       Pa     m**3   kmol
+   *  1  VCS_UNITS_KJMOL    = kJ / gmol                 Pa     m**3   kmol
+   *  2  VCS_UNITS_KELVIN   = KELVIN -> MU / R          Pa     m**3   kmol
    *  3  VCS_UNITS_MKS      = Joules / Kmol (Cantera)   Pa     m**3   kmol
    * ----------------------------------------------------------------------
    *
@@ -358,15 +364,13 @@ public:
  
   //! Vector of the Star molar Volumes of the species.
   /*!
-   * units depends on VCS_UnitsFormat variable
-   *             Cantera -> m3 / kmol
+   * units  m3 / kmol
    */
   mutable std::vector<double> StarMolarVol;
 
   //! Vector of the Partial molar Volumes of the species.
   /*!
-   * units depends on VCS_UnitsFormat variable
-   *             Cantera -> m3 / kmol
+   * units  m3 / kmol
    */
   mutable std::vector<double> PartialMolarVol;
 
@@ -591,6 +595,8 @@ public:
    *
    * @param TKelvin Current temperature
    * @param pres    Current pressure
+   *
+   *  Units are in m**3/kmol
    */
   void VolStar_calc(double TKelvin, double pres);
 
@@ -605,7 +611,7 @@ public:
    * @param pres    Current pressure
    *
    * @return molar volume of the kspec species's standard
-   *         state
+   *         state (m**3/kmol)
    */
   double VolStar_calc_one(int kglob, double TKelvin, double pres);
 
diff --git a/Cantera/src/equil/vcs_defs.h b/Cantera/src/equil/vcs_defs.h
index 1a00282f6..42046a326 100644
--- a/Cantera/src/equil/vcs_defs.h
+++ b/Cantera/src/equil/vcs_defs.h
@@ -191,10 +191,10 @@ namespace VCSnonideal {
    * @verbatim
                          Chem_Pot                 Pres      vol   moles
                            -------------------------------------------------
-     VCS_UNITS_KCALMOL  = kcal/mol                  atm   cm**3   gmol
-     VCS_UNITS_UNITLESS = MU / RT -> no units       atm   cm**3   gmol
-     VCS_UNITS_KJMOL    = kJ / mol                  atm   cm**3   gmol
-     VCS_UNITS_KELVIN   = KELVIN -> MU / R          atm   cm**3   gmol
+     VCS_UNITS_KCALMOL  = kcal/mol                  Pa     m**3   kmol
+     VCS_UNITS_UNITLESS = MU / RT -> no units       Pa     m**3   kmol
+     VCS_UNITS_KJMOL    = kJ / mol                  Pa     m**3   kmol
+     VCS_UNITS_KELVIN   = KELVIN -> MU / R          Pa     m**3   kmol
      VCS_UNITS_MKS      = Joules / Kmol (Cantera)   Pa     m**3   kmol
    
              Energy:
@@ -205,10 +205,10 @@ namespace VCSnonideal {
                 VCS_UNITS_MKS      = J / kmol
    
              Pressure: (Pref and Pres)
-                VCS_UNITS_KCALMOL  = atm
-                VCS_UNITS_UNITLESS = no units
-                VCS_UNITS_KJMOL    = atm
-                VCS_UNITS_KELVIN   = atm
+                VCS_UNITS_KCALMOL  = Pa
+                VCS_UNITS_UNITLESS = Pa
+                VCS_UNITS_KJMOL    = Pa
+                VCS_UNITS_KELVIN   = Pa
                 VCS_UNITS_MKS      = Pa = kg / m s2
     @endverbatim
    * @{
diff --git a/Cantera/src/equil/vcs_nondim.cpp b/Cantera/src/equil/vcs_nondim.cpp
index fca355ce9..e8fe67ca2 100644
--- a/Cantera/src/equil/vcs_nondim.cpp
+++ b/Cantera/src/equil/vcs_nondim.cpp
@@ -113,11 +113,13 @@ void VCS_SOLVE::vcs_nondim_TP(void) {
       if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
 	for (i = 0; i < m_numSpeciesTot; ++i) {
 	  if (SpeciesUnknownType[i] != VCS_SPECIES_TYPE_INTERFACIALVOLTAGE) {
-	    m_molNumSpecies_old[i] *= 1.0E3;
+	    //m_molNumSpecies_old[i] *= 1.0E3;
+	    m_molNumSpecies_old[i] *= 1.0;
 	  }
 	}
 	for (i = 0; i < m_numElemConstraints; ++i) {
-	  m_elemAbundancesGoal[i] *= 1.0E3;
+	  //m_elemAbundancesGoal[i] *= 1.0E3;
+	  m_elemAbundancesGoal[i] *= 1.0;
 	}
       }
     }
@@ -153,11 +155,13 @@ void VCS_SOLVE::vcs_redim_TP(void)
     if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
 	for (i = 0; i < m_numSpeciesTot; ++i) {
 	  if (SpeciesUnknownType[i] != VCS_SPECIES_TYPE_INTERFACIALVOLTAGE) {
-	    m_molNumSpecies_old[i] /= 1.0E3;
+	    //m_molNumSpecies_old[i] /= 1.0E3;
+	    m_molNumSpecies_old[i] /= 1.0;
 	  }
 	}
 	for (i = 0; i < m_numElemConstraints; ++i) {
-	  m_elemAbundancesGoal[i] /= 1.0E3;
+	  //m_elemAbundancesGoal[i] /= 1.0E3;
+	  m_elemAbundancesGoal[i] /= 1.0;
 	}
     }
 
diff --git a/Cantera/src/equil/vcs_prep.cpp b/Cantera/src/equil/vcs_prep.cpp
index 5f6c28cec..f2b4a3fd0 100644
--- a/Cantera/src/equil/vcs_prep.cpp
+++ b/Cantera/src/equil/vcs_prep.cpp
@@ -191,8 +191,8 @@ int VCS_SOLVE::vcs_prep_oneTime(int printLvl)
     }
     if (fabs(sum) < 1.0E-6) {
       modifiedSoln = true;
-      if (m_pressure <= 0.0)    pres = 1.0;
-      else                      pres = m_pressure;
+      if (m_pressurePA <= 0.0)  pres = 1.01325E5;
+      else                      pres = m_pressurePA;
       retn = vcs_evalSS_TP(0, 0, m_temperature, pres);
       for (kspec = 0; kspec < m_numSpeciesTot; ++kspec) {
 	if (SpeciesUnknownType[kspec] == VCS_SPECIES_TYPE_MOLNUM) {
diff --git a/Cantera/src/equil/vcs_prob.cpp b/Cantera/src/equil/vcs_prob.cpp
index a62cd4fd8..b1892580a 100644
--- a/Cantera/src/equil/vcs_prob.cpp
+++ b/Cantera/src/equil/vcs_prob.cpp
@@ -42,7 +42,7 @@ VCS_PROB::VCS_PROB(int nsp, int nel, int nph) :
     NPhase(nph),
     NPHASE0(0),
     T(298.15),
-    Pres(1.0),
+    PresPA(1.0),
     Vol(0.0),
     m_VCS_UnitsFormat(VCS_UNITS_UNITLESS),  
     /* Set the units for the chemical potential data to be
@@ -243,10 +243,8 @@ void VCS_PROB::prob_report(int print_lvl) {
     if (prob_type == 0) {
       plogf("\tSolve a constant T, P problem:\n");
       plogf("\t\tT    = %g K\n", T);
-      double pres_atm = Pres;
-      if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
-	pres_atm = Pres / 1.0133E5;
-      }
+      double pres_atm = PresPA / 1.01325E5;
+      
       plogf("\t\tPres = %g atm\n", pres_atm);
     } else {
       plogf("\tUnknown problem type\n");
@@ -279,7 +277,7 @@ void VCS_PROB::prob_report(int print_lvl) {
     plogf("             Information about phases\n");
     plogf("  PhaseName    PhaseNum SingSpec  GasPhase   "
 	   " EqnState    NumSpec");
-    plogf("  TMolesInert       Tmoles\n");
+    plogf("  TMolesInert      TKmoles\n");
    
     for (iphase = 0; iphase < NPhase; iphase++) {
       Vphase = VPhaseList[iphase];
@@ -293,10 +291,11 @@ void VCS_PROB::prob_report(int print_lvl) {
     }
 
     plogf("\nElemental Abundances:    ");
-    plogf("         Target_gmol    ElemType ElActive\n");
+    plogf("         Target_kmol    ElemType ElActive\n");
     double fac = 1.0;
     if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
-      fac = 1.0E3;
+      //fac = 1.0E3;
+      fac = 1.0;
     }
     for (i = 0; i < ne; ++i) {
       print_space(26); plogf("%-2.2s", ElName[i].c_str());
@@ -322,7 +321,7 @@ void VCS_PROB::prob_report(int print_lvl) {
     for (iphase = 0; iphase < NPhase; iphase++) {
       Vphase = VPhaseList[iphase];
       Vphase->G0_calc(T);
-      Vphase->GStar_calc(T, Pres);
+      Vphase->GStar_calc(T, PresPA);
       for (int kindex = 0; kindex < Vphase->NVolSpecies; kindex++) {
 	int kglob = Vphase->IndSpecies[kindex];
 	plogf("%16s ", SpName[kglob].c_str());
@@ -475,7 +474,6 @@ void VCS_PROB::reportCSV(const std::string &reportFile) {
     exit(-1);
   }
   double Temp = T;
-  double pres = Pres;
 
   std::vector<double> volPM(nspecies, 0.0);
   std::vector<double> activity(nspecies, 0.0);;
@@ -508,7 +506,7 @@ void VCS_PROB::reportCSV(const std::string &reportFile) {
   fprintf(FP,"--------------------- VCS_MULTIPHASE_EQUIL FINAL REPORT"
 	  " -----------------------------\n");
   fprintf(FP,"Temperature  = %11.5g kelvin\n", Temp);
-  fprintf(FP,"Pressure     = %11.5g Pascal\n", pres);
+  fprintf(FP,"Pressure     = %11.5g Pascal\n", PresPA);
   fprintf(FP,"Total Volume = %11.5g m**3\n", vol);
   fprintf(FP,"Number Basis optimizations = %d\n", m_NumBasisOptimizations);
   fprintf(FP,"Number VCS iterations = %d\n", m_Iterations);
diff --git a/Cantera/src/equil/vcs_prob.h b/Cantera/src/equil/vcs_prob.h
index e85924e51..0b6e09312 100644
--- a/Cantera/src/equil/vcs_prob.h
+++ b/Cantera/src/equil/vcs_prob.h
@@ -136,8 +136,9 @@ namespace VCSnonideal {
     //! Pressure
     /*!
      * units given by m_VCS_UnitsFormat
+     * -> are now PA 
      */
-    double Pres;
+    double PresPA;
 
     //! Volume of the entire system
     /*!
diff --git a/Cantera/src/equil/vcs_report.cpp b/Cantera/src/equil/vcs_report.cpp
index 2341b20a2..88e9bb651 100644
--- a/Cantera/src/equil/vcs_report.cpp
+++ b/Cantera/src/equil/vcs_report.cpp
@@ -105,23 +105,19 @@ int VCS_SOLVE::vcs_report(int iconv)
    *   Calculate some quantities that may need updating
    */
    vcs_tmoles();
-   Vol = vcs_VolTotal(m_temperature, m_pressure, 
+   Vol = vcs_VolTotal(m_temperature, m_pressurePA, 
 		      VCS_DATA_PTR(m_molNumSpecies_old), VCS_DATA_PTR(VolPM));
    
    plogf("\t\tTemperature = %15.2g Kelvin\n", m_temperature);
-   std::string punits = "Atm";
-   if (m_VCS_UnitsFormat == 3) {
-     punits = "Pa ";
-   }
-   plogf("\t\tPressure    = %15.5g %3s\n", m_pressure, punits.c_str()); 
-   plogf("\t\tVolume      = %15.5g cm**3\n", Vol);
+   plogf("\t\tPressure    = %15.5g Pa \n", m_pressurePA); 
+   plogf("\t\tVolume      = %15.5g m**3\n", Vol);
    
    /* 
     * -------- TABLE OF SPECIES IN DECREASING MOLE NUMBERS --------------
     */
    plogf("\n\n");
    print_line("-", 80);
-   plogf(" Species                 Equilibrium moles    ");
+   plogf(" Species                 Equilibrium kmoles   ");
    plogf("Mole Fraction    ChemPot/RT    SpecUnkType\n");
    print_line("-", 80);
    for (i = 0; i < m_numComponents; ++i) {
@@ -138,7 +134,7 @@ int VCS_SOLVE::vcs_report(int iconv)
      
       if (SpeciesUnknownType[l] == VCS_SPECIES_TYPE_MOLNUM) {
 	plogf("%14.7E     %14.7E    %12.4E", m_molNumSpecies_old[l], m_molNumSpecies_new[l], m_feSpecies_curr[l]);
-	plogf("   MolNum ");
+	plogf("  KMolNum ");
       } else if (SpeciesUnknownType[l] == VCS_SPECIES_TYPE_INTERFACIALVOLTAGE) {
 	plogf("        NA         %14.7E    %12.4E", 1.0, m_feSpecies_curr[l]);
 	plogf("   Voltage = %14.7E", m_molNumSpecies_old[l]);
@@ -162,13 +158,13 @@ int VCS_SOLVE::vcs_report(int iconv)
       }
    }
    if (m_numSpeciesRdc != nspecies) {
-      plogf("\n SPECIES WITH LESS THAN 1.0E-32 MOLES:\n\n");
+      plogf("\n SPECIES WITH LESS THAN 1.0E-32 KMOLES:\n\n");
       for (kspec = m_numSpeciesRdc; kspec < nspecies; ++kspec) {
 	 plogf(" %-12.12s", SpName[kspec].c_str());
 	 plogf("             %14.7E     %14.7E    %12.4E",
 		m_molNumSpecies_old[kspec], m_molNumSpecies_new[kspec], m_deltaGRxn_new[kspec]);
 	 if (SpeciesUnknownType[i] == VCS_SPECIES_TYPE_MOLNUM) {
-	   plogf("   Mol_Num");
+	   plogf("  KMol_Num");
 	 } else if (SpeciesUnknownType[i] == VCS_SPECIES_TYPE_INTERFACIALVOLTAGE) {
 	   plogf("   Voltage");
 	 } else {
@@ -237,7 +233,7 @@ int VCS_SOLVE::vcs_report(int iconv)
      plogf(" %10.10s", (ElName[j]).c_str());
    }
    plogf(" |                     |\n");
-   plogf("    PhaseName     | MolTarget |");
+   plogf("    PhaseName     |KMolTarget |");
    for (j = 0; j < m_numElemConstraints; j++) {
      plogf(" %10.3g", m_elemAbundancesGoal[j]);
    }
@@ -291,7 +287,7 @@ int VCS_SOLVE::vcs_report(int iconv)
    if (inertYes) 
       plogf("\t\t(Inert species have standard free energy of zero)\n");
    
-   plogf("\nElemental Abundances:     ");
+   plogf("\nElemental Abundances (kmol): ");
    plogf("         Actual                    Target         Type      ElActive\n");
    for (i = 0; i < m_numElemConstraints; ++i) {
       print_space(26); plogf("%-2.2s", (ElName[i]).c_str());
@@ -310,7 +306,7 @@ int VCS_SOLVE::vcs_report(int iconv)
    plogf("\t\t(RT = %g ", rt);
    vcs_printChemPotUnits(m_VCS_UnitsFormat);
    plogf(")\n");
-   plogf("    Name         TMoles     StandStateChemPot   "
+   plogf("    Name        TKMoles     StandStateChemPot   "
 	  "   ln(AC)       ln(X_i)      |   F z_i phi   |    ChemPot    | (-lnMnaught)\n");
    print_line("-", 115);
    for (i = 0; i < nspecies; ++i) {
diff --git a/Cantera/src/equil/vcs_solve.cpp b/Cantera/src/equil/vcs_solve.cpp
index 0168c5f4c..09eee6c83 100644
--- a/Cantera/src/equil/vcs_solve.cpp
+++ b/Cantera/src/equil/vcs_solve.cpp
@@ -44,7 +44,7 @@ namespace VCSnonideal {
     iest(0),
     TMoles(0.0),
     m_temperature(0.0),
-    m_pressure(0.0),
+    m_pressurePA(0.0),
     tolmaj(0.0),
     tolmin(0.0),
     tolmaj2(0.0),
@@ -389,7 +389,7 @@ namespace VCSnonideal {
        *    calculate the residual and Jacobian)
        */
     
-      iconv = vcs_TP(ipr, ip1, maxit, vprob->T, vprob->Pres);
+      iconv = vcs_TP(ipr, ip1, maxit, vprob->T, vprob->PresPA);
 
 	     
       /*
@@ -582,8 +582,8 @@ namespace VCSnonideal {
      */
     if (pub->T  > 0.0)  m_temperature = pub->T;
     else                m_temperature = 293.15;
-    if (pub->Pres > 0.0) m_pressure = pub->Pres;
-    else                 m_pressure = 1.0;
+    if (pub->PresPA > 0.0) m_pressurePA = pub->PresPA;
+    else                   m_pressurePA = Cantera::OneAtm;
     /*
      *   TPhInertMoles[] -> must be copied over here
      */
@@ -773,7 +773,7 @@ namespace VCSnonideal {
     bool status_change = false;
 
     m_temperature = pub->T;
-    m_pressure = pub->Pres;
+    m_pressurePA = pub->PresPA;
     m_VCS_UnitsFormat = pub->m_VCS_UnitsFormat;
     iest = pub->iest;
 
@@ -902,7 +902,7 @@ namespace VCSnonideal {
     int k1 = 0;
 
     vcs_tmoles();
-    Vol = vcs_VolTotal(m_temperature, m_pressure, 
+    Vol = vcs_VolTotal(m_temperature, m_pressurePA, 
 		       VCS_DATA_PTR(m_molNumSpecies_old), VCS_DATA_PTR(VolPM));
 
     for (i = 0; i < m_numSpeciesTot; ++i) {
@@ -930,7 +930,7 @@ namespace VCSnonideal {
     } 
    
     pub->T    = m_temperature;
-    pub->Pres = m_pressure;
+    pub->PresPA = m_pressurePA;
     pub->Vol  = Vol;
     int kT = 0;
     for (int iph = 0; iph < pub->NPhase; iph++) {
diff --git a/Cantera/src/equil/vcs_solve.h b/Cantera/src/equil/vcs_solve.h
index d27595476..878c977ab 100644
--- a/Cantera/src/equil/vcs_solve.h
+++ b/Cantera/src/equil/vcs_solve.h
@@ -621,7 +621,7 @@ public:
    *  Note other constraint conditions are added to this vector.
    *  This is input from the input file and 
    *  is considered a constant from thereon.
-   *   units = gmoles
+   *   units = kmoles
    */
   std::vector<double> m_elemAbundances;
 
@@ -632,7 +632,7 @@ public:
    *  Note other constraint conditions are added to this vector.
    *  This is input from the input file and 
    *  is considered a constant from thereon.
-   *   units = gmoles 
+   *   units = kmoles 
    */
   std::vector<double> m_elemAbundancesGoal; 
 
@@ -641,7 +641,7 @@ public:
 		     *            -> Don't use this except for scaling
 		     *               purposes only                          */
 
-  //! total gmols of species in each phase
+  //! total kmols of species in each phase
   /*!
    *  This contains the total number of moles of species in each phase
    *
@@ -649,7 +649,7 @@ public:
    */
   std::vector<double> m_tPhaseMoles_old;
 
-  //! total gmols of species in each phase in the tentative soln vector
+  //! total kmols of species in each phase in the tentative soln vector
   /*!
    *  This contains the total number of moles of species in each phase
    *  in the tentative solution vector
@@ -681,12 +681,13 @@ public:
    *                1:  atm
    *                2:  atm
    *                3:  Pa
+   *   Units being changed to Pa
    */
-  double   m_pressure;
+  double   m_pressurePA;
 
   //!  Total kmoles of inert to add to each phase 
   /*!
-   *  TPhInertMoles[iph] = Total gmoles of  inert to add to each phase
+   *  TPhInertMoles[iph] = Total kmoles of  inert to add to each phase
    *  length = number of phases
    */
   std::vector<double> TPhInertMoles; 
@@ -864,7 +865,7 @@ public:
 
   //! Molecular weight of each species
   /*!
-   *  units = gm/gmol
+   *  units = kg/kmol
    *  length = number of species
    */
   std::vector<double> WtSpecies;
@@ -891,7 +892,7 @@ public:
    */
   int UseActCoeffJac;
 
-  double   Vol;     /* Vol        = Volume (cm^3) */
+  double   Vol;     /* Vol        = Volume (m^3) */
   
   //! Partialm molar volumes of the species
   /*!
@@ -928,10 +929,10 @@ public:
    *                           2:  Kelvin 
    *                           3:  J / kmol 
    *                    and pressure data:
-   *                          -1:  atm
-   *                           0:  atm
-   *                           1:  atm
-   *                           2:  atm
+   *                          -1:  Pa
+   *                           0:  Pa
+   *                           1:  Pa
+   *                           2:  pa
    *                           3:  Pa
    */
   int m_VCS_UnitsFormat;
diff --git a/Cantera/src/equil/vcs_solve_TP.cpp b/Cantera/src/equil/vcs_solve_TP.cpp
index 4332f5dc9..caa209a76 100644
--- a/Cantera/src/equil/vcs_solve_TP.cpp
+++ b/Cantera/src/equil/vcs_solve_TP.cpp
@@ -237,11 +237,11 @@ namespace VCSnonideal {
       plogf("%10d PHASE2 SPECIES%8d SINGLE SPECIES PHASES\n\n", 
 	    numSpecliquid, 
 	    m_numSpeciesTot - (VPhaseList[0])->NVolSpecies - numSpecliquid);  
-      string punits = "atm";
-      if (m_VCS_UnitsFormat == 3) {
-	punits = "Pa ";
-      }
-      plogf(" PRESSURE%22.8g %3s\n", m_pressure, punits.c_str()); 
+      //string punits = "atm";
+      //if (m_VCS_UnitsFormat == 3) {
+      //	punits = "Pa ";
+      //}
+      plogf(" PRESSURE%22.8g %3s\n", m_pressurePA, "Pa "); 
       plogf(" TEMPERATURE%19.3f K\n", m_temperature);
       Vphase = VPhaseList[0];
       if (Vphase->NVolSpecies > 0) {
@@ -532,7 +532,7 @@ namespace VCSnonideal {
       if (iti == 0) plogf("- Full Calculation:\n");
       else          plogf("- Major Components Calculation:\n");
       plogf("   --- Species     IC    ");
-      plogf(" Moles   Tent_Moles  Rxn_Adj   |    Comment \n");
+      plogf(" KMoles  Tent_KMoles Rxn_Adj   |    Comment \n");
     }
 #endif
    
@@ -785,7 +785,7 @@ namespace VCSnonideal {
 	 */
 	if (m_molNumSpecies_new[kspec] <= 0.0) {
 #ifdef DEBUG_MODE
-	  sprintf(ANOTE, "initial nonpos moles= %11.3E",
+	  sprintf(ANOTE, "initial nonpos kmoles= %11.3E",
 		  m_molNumSpecies_new[kspec]);
 #endif
 	  /* ************************************************* */
@@ -801,7 +801,7 @@ namespace VCSnonideal {
 	  if (! (SSPhase[kspec])) {
 	    /* 
 	     *   Section for multispecies phases:
-	     *     - Cut reaction adjustment for positive moles of 
+	     *     - Cut reaction adjustment for positive kmoles of 
 	     *       major species in multispecies phases.
 	     *       Decrease its concentration by a factor of 10.
 	     */
@@ -811,7 +811,7 @@ namespace VCSnonideal {
 	    /*
 	     *        Change major to minor if the current species
 	     *        has a mole number that is less than 1/100 of the
-	     *        total moles in the problem.
+	     *        total kmoles in the problem.
 	     *        However, it also has to be a small species within its
 	     *        own phase as well.
 	     *        we can't call vcs_species_type() because the phase moles
@@ -954,7 +954,7 @@ namespace VCSnonideal {
 
       } /* End of Loop on ic[irxn] -> the type of species */
       /***********************************************************************/
-      /****** CALCULATE MOLE NUMBER CHANGE FOR THE COMPONENT BASIS ***********/
+      /****** CALCULATE KMOLE NUMBER CHANGE FOR THE COMPONENT BASIS **********/
       /***********************************************************************/
       if (dx != 0.0 && (SpeciesUnknownType[kspec] != VCS_SPECIES_TYPE_INTERFACIALVOLTAGE)) {
 	/*
@@ -1143,7 +1143,7 @@ namespace VCSnonideal {
       plogf(" -----------------------------------------------------\n");
       plogf("   --- FORCER SUBROUTINE changed the solution:\n");
       plogf("   --- SPECIES Status INIT MOLES TENT_MOLES");
-      plogf("  FINAL MOLES   INIT_DEL_G/RT  TENT_DEL_G/RT  FINAL_DELTA_G/RT\n");
+      plogf("  FINAL KMOLES  INIT_DEL_G/RT  TENT_DEL_G/RT  FINAL_DELTA_G/RT\n");
       for (i = 0; i < m_numComponents; ++i) {
 	plogf("  --- %-12.12s", SpName[i].c_str());
 	plogf("    %14.6E %14.6E %14.6E\n",  m_molNumSpecies_old[i], m_molNumSpecies_old[i] + m_deltaMolNumSpecies[i], m_molNumSpecies_new[i]);
@@ -1160,11 +1160,11 @@ namespace VCSnonideal {
       plogf("Norms of Delta G():%14.6E%14.6E\n",
 	    l2normdg(VCS_DATA_PTR(m_deltaGRxn_old)),
 	    l2normdg(VCS_DATA_PTR(m_deltaGRxn_new)));
-      plogf("   Total moles of gas    = %15.7E\n", m_tPhaseMoles_old[0]);
+      plogf("   Total kmoles of gas    = %15.7E\n", m_tPhaseMoles_old[0]);
       if ((NPhase > 1) && (! (VPhaseList[1])->SingleSpecies)) { 
-	plogf("   Total moles of liquid = %15.7E\n", m_tPhaseMoles_old[1]); 
+	plogf("   Total kmoles of liquid = %15.7E\n", m_tPhaseMoles_old[1]); 
       } else {
-	plogf("   Total moles of liquid = %15.7E\n", 0.0);
+	plogf("   Total kmoles of liquid = %15.7E\n", 0.0);
       }
       plogf("   Total New Dimensionless Gibbs Free Energy = %20.13E\n", 
 	    vcs_Total_Gibbs(VCS_DATA_PTR(m_molNumSpecies_new), VCS_DATA_PTR(m_feSpecies_curr),
@@ -1185,7 +1185,7 @@ namespace VCSnonideal {
       } else {
 	plogf(" (only major species):\n");
       }
-      plogf("   ---      Species Status Initial_Moles  Final_Moles  Initial_Mu/RT");
+      plogf("   ---      Species Status Initial_KMoles Final_KMoles Initial_Mu/RT");
       plogf("     Mu/RT     Init_Del_G/RT   Delta_G/RT\n");
       for (i = 0; i < m_numComponents; ++i) {
 	plogf("   ---   %-12.12s", SpName[i].c_str()); plogf("    "); 
@@ -1214,7 +1214,7 @@ namespace VCSnonideal {
 	    l2normdg(VCS_DATA_PTR(m_deltaGRxn_new)));
       plogendl();
       
-      plogf("   ---           Phase_Name     Moles(after update)\n");
+      plogf("   ---           Phase_Name    KMoles(after update)\n");
       plogf("   ---   "); vcs_print_line("-", 50);
       for (iph = 0; iph < NPhase; iph++) {
 	Vphase = VPhaseList[iph];
@@ -2129,7 +2129,7 @@ namespace VCSnonideal {
      *
      *  Change the concentration of a species by delta moles. 
      *  Make sure to conserve
-     *  elements and keep track of the total moles in all phases.
+     *  elements and keep track of the total kmoles in all phases.
      *
      *  return:
      *      1: succeeded
@@ -2831,7 +2831,7 @@ namespace VCSnonideal {
       plogf("   "); for (j = 0; j < 82; j++) plogf("-"); plogf("\n");
       plogf("   --- Subroutine vcs_RxnStepSizes called - Details:\n");
       plogf("   "); for (j = 0; j < 82; j++) plogf("-"); plogf("\n");
-      plogf("   --- Species         Moles     Rxn_Adjustment    DeltaG"
+      plogf("   --- Species        KMoles     Rxn_Adjustment    DeltaG"
 	    "   | Comment\n");
     }
 #endif
diff --git a/Cantera/src/equil/vcs_species_thermo.cpp b/Cantera/src/equil/vcs_species_thermo.cpp
index e1e463bc1..c3baace58 100644
--- a/Cantera/src/equil/vcs_species_thermo.cpp
+++ b/Cantera/src/equil/vcs_species_thermo.cpp
@@ -43,7 +43,7 @@ VCS_SPECIES_THERMO::VCS_SPECIES_THERMO(int indexPhase,
   SS0_H0(0.0),
   SS0_S0(0.0),
   SS0_Cp0(0.0),
-  SS0_Pref(1.0),
+  SS0_Pref(1.01325E5),
   SS0_Params(0),
   SSStar_Model(VCS_SSSTAR_CONSTANT),
   SSStar_Params(0),
@@ -55,15 +55,7 @@ VCS_SPECIES_THERMO::VCS_SPECIES_THERMO(int indexPhase,
   UseCanteraCalls(false),
   m_VCS_UnitsFormat(VCS_UNITS_UNITLESS)
 {
-  /*
-   * Set up the numerical value for P_reference, based on the current
-   * global units choice.
-   */
-  if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
-    SS0_Pref = 1.0133E5;
-  } else {
-    SS0_Pref = 1.0;
-  }
+  SS0_Pref = 1.01325E5;
 }
 
 
@@ -224,11 +216,11 @@ double VCS_SPECIES_THERMO::GStar_R_calc(int kglob, double TKelvin,
  *  Input
  *
  * Output
- *    return value = standard state volume in    cm**3 per mol.
- *                   (VCS_UNITS_MKS)              m**3 / kmol
+ *    return value = standard state volume in    m**3 per kmol.
+ *                   (VCS_UNITS_MKS)  
  */
 double VCS_SPECIES_THERMO::
-VolStar_calc(int kglob, double TKelvin, double pres)
+VolStar_calc(int kglob, double TKelvin, double presPA)
 {
   char yo[] = "VCS_SPECIES_THERMO::VStar_calc ";
   double vol, T;
@@ -237,18 +229,15 @@ VolStar_calc(int kglob, double TKelvin, double pres)
   if (UseCanteraCalls) {
     AssertThrowVCS(m_VCS_UnitsFormat == VCS_UNITS_MKS, "Possible inconsistency");
     int kspec = IndexSpeciesPhase;
-    vol = OwningPhase->VolStar_calc_one(kspec, TKelvin, pres);
+    vol = OwningPhase->VolStar_calc_one(kspec, TKelvin, presPA);
   } else {
     switch(SSStar_Vol_Model) {
     case VCS_SSVOL_CONSTANT:
       vol = SSStar_Vol0;
       break;
     case VCS_SSVOL_IDEALGAS:
-      if (m_VCS_UnitsFormat == VCS_UNITS_MKS) {
-	vol = 8.31451E3 * T / pres;
-      } else {
-	vol= 83.14510 / 1.01325 * T / pres;	 
-      }
+      // R J/kmol/K (2006 CODATA value)
+      vol= 8314.47215  * T / presPA;
       break;
     default:     
       plogf("%sERROR: unknown SSVol model\n", yo);
diff --git a/Cantera/src/equil/vcs_species_thermo.h b/Cantera/src/equil/vcs_species_thermo.h
index e7e68e9ca..268b9731f 100644
--- a/Cantera/src/equil/vcs_species_thermo.h
+++ b/Cantera/src/equil/vcs_species_thermo.h
@@ -112,6 +112,7 @@ public:
 
   /**
    * Value of the pressure for the reference state.
+   *  defaults to 1.01325E5 = 1 atm
    */
   double SS0_Pref;
   /**