diff --git a/src/pamm/PammObject.cpp b/src/pamm/PammObject.cpp
index 54430672297d8d6c09ded516a7652f4f1f86e733..7606d7f1beb50aba419b216a9f55fccc7a1e4be2 100644
--- a/src/pamm/PammObject.cpp
+++ b/src/pamm/PammObject.cpp
@@ -21,6 +21,7 @@
 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
 #include "PammObject.h"
 #include "tools/IFile.h"
+#include <memory>
 
 namespace PLMD {
 namespace pamm {
@@ -65,10 +66,11 @@ void PammObject::setup( const std::string& filename, const double& reg, const st
 
   ifile.open(filename); ifile.allowIgnoredFields(); kernels.resize(0);
   for(unsigned k=0;; ++k) {
-    KernelFunctions* kk = KernelFunctions::read( &ifile, false, valnames );
+    std::unique_ptr<KernelFunctions> kk = KernelFunctions::read( &ifile, false, valnames );
     if( !kk ) break ;
     kk->normalize( pos );
-    kernels.push_back( kk );
+    kernels.push_back( kk.release() ); // kernels should be changed into a vector<unique_ptr>.
+    // meanwhile, I just release the unique_ptr herelease the unique_ptr here. GB
     ifile.scanField();
   }
   ifile.close();
diff --git a/src/tools/BiasRepresentation.cpp b/src/tools/BiasRepresentation.cpp
index c81524de749babb92f54e757c1b2d15a2053d7c5..bafae408da3afbd2642e5d826114955cf795ae42 100644
--- a/src/tools/BiasRepresentation.cpp
+++ b/src/tools/BiasRepresentation.cpp
@@ -115,24 +115,24 @@ Value*  BiasRepresentation::getPtrToValue(unsigned i) {
   return values[i];
 }
 
-KernelFunctions* BiasRepresentation::readFromPoint(IFile *ifile) {
+std::unique_ptr<KernelFunctions> BiasRepresentation::readFromPoint(IFile *ifile) {
   vector<double> cc( names.size() );
   for(unsigned i=0; i<names.size(); ++i) {
     ifile->scanField(names[i],cc[i]);
   }
   double h=1.0;
-  return new KernelFunctions(cc,histosigma,"gaussian","DIAGONAL",h);
+  return std::unique_ptr<KernelFunctions>( new KernelFunctions(cc,histosigma,"gaussian","DIAGONAL",h) );
 }
 void BiasRepresentation::pushKernel( IFile *ifile ) {
   std::unique_ptr<KernelFunctions> kk;
   // here below the reading of the kernel is completely hidden
   if(histosigma.size()==0) {
     ifile->allowIgnoredFields();
-    kk.reset(KernelFunctions::read(ifile,true,names));
+    kk=KernelFunctions::read(ifile,true,names);
   } else {
     // when doing histogram assume gaussian with a given diagonal sigma
     // and neglect all the rest
-    kk.reset(readFromPoint(ifile));
+    kk=readFromPoint(ifile);
   }
   // the bias factor is not something about the kernels but
   // must be stored to keep the  bias/free energy duality
diff --git a/src/tools/BiasRepresentation.h b/src/tools/BiasRepresentation.h
index a775a0120cdc6bde5327121529c0a060e65bf880..93c613a34654370300eee16171daffaf76669bcb 100644
--- a/src/tools/BiasRepresentation.h
+++ b/src/tools/BiasRepresentation.h
@@ -76,7 +76,7 @@ public:
   /// get the pointer to the grid
   Grid* 	getGridPtr();
   /// get a new histogram point from a file
-  KernelFunctions* readFromPoint(IFile *ifile);
+  std::unique_ptr<KernelFunctions> readFromPoint(IFile *ifile);
   /// get an automatic min/max from the set so to know how to configure the grid
   void getMinMaxBin(std::vector<double> &vmin, std::vector<double> &vmax, std::vector<unsigned> &vbin);
   /// clear the representation (grid included)
diff --git a/src/tools/KernelFunctions.cpp b/src/tools/KernelFunctions.cpp
index f9f61cd375dcf36cb5463ac815df46ff7c420e2b..deea4c209c27a46d2caafb6c502e10004f4947aa 100755
--- a/src/tools/KernelFunctions.cpp
+++ b/src/tools/KernelFunctions.cpp
@@ -382,7 +382,7 @@ double KernelFunctions::evaluate( const std::vector<Value*>& pos, std::vector<do
   return kval;
 }
 
-KernelFunctions* KernelFunctions::read( IFile* ifile, const bool& cholesky, const std::vector<std::string>& valnames ) {
+std::unique_ptr<KernelFunctions> KernelFunctions::read( IFile* ifile, const bool& cholesky, const std::vector<std::string>& valnames ) {
   double h;
   if( !ifile->scanField("height",h) ) return NULL;;
 
@@ -401,7 +401,7 @@ KernelFunctions* KernelFunctions::read( IFile* ifile, const bool& cholesky, cons
       ifile->scanField("sigma_"+valnames[i],sig[i]);
       if( !cholesky ) sig[i]=sqrt(sig[i]);
     }
-    return new KernelFunctions( cc, sig, ktype, "DIAGONAL", h );
+    return std::unique_ptr<KernelFunctions>(new KernelFunctions( cc, sig, ktype, "DIAGONAL", h ) );
   }
 
   unsigned ncv=valnames.size();
@@ -419,8 +419,8 @@ KernelFunctions* KernelFunctions::read( IFile* ifile, const bool& cholesky, cons
   for(unsigned i=0; i<ncv; i++) {
     for(unsigned j=i; j<ncv; j++) { sig[k]=invmatrix(i,j); k++; }
   }
-  if( sss=="true" ) return new KernelFunctions( cc, sig, ktype, "MULTIVARIATE", h );
-  return new KernelFunctions( cc, sig, ktype, "VON-MISSES", h );
+  if( sss=="true" ) return std::unique_ptr<KernelFunctions>(new KernelFunctions( cc, sig, ktype, "MULTIVARIATE", h ) );
+  return std::unique_ptr<KernelFunctions>(new KernelFunctions( cc, sig, ktype, "VON-MISSES", h ) );
 }
 
 }
diff --git a/src/tools/KernelFunctions.h b/src/tools/KernelFunctions.h
index 32966973eba45d7bdb1ce358a16705428a9dd8cd..ac26c23d33291bc8692ceff0cf9ec7d6be3241f0 100644
--- a/src/tools/KernelFunctions.h
+++ b/src/tools/KernelFunctions.h
@@ -26,6 +26,7 @@
 #include "Matrix.h"
 #include "core/Value.h"
 #include <vector>
+#include <memory>
 
 namespace PLMD {
 
@@ -64,7 +65,7 @@ public:
 /// Evaluate the kernel function with constant intervals
   double evaluate( const std::vector<Value*>& pos, std::vector<double>& derivatives, bool usederiv=true, bool doInt=false, double lowI_=-1, double uppI_=-1 ) const;
 /// Read a kernel function from a file
-  static KernelFunctions* read( IFile* ifile, const bool& cholesky, const std::vector<std::string>& valnames );
+  static std::unique_ptr<KernelFunctions> read( IFile* ifile, const bool& cholesky, const std::vector<std::string>& valnames );
 };
 
 inline