diff --git a/src/pair_coul_dsf.cpp b/src/pair_coul_dsf.cpp
new file mode 100644
index 0000000000..ff3f73ad92
--- /dev/null
+++ b/src/pair_coul_dsf.cpp
@@ -0,0 +1,337 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under 
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+/* ----------------------------------------------------------------------
+   Contributing author: Trung Dac Nguyen (ORNL)
+   References: Fennell and Gezelter, JCP 124, 234104 (2006)
+------------------------------------------------------------------------- */
+
+#include "math.h"
+#include "stdio.h"
+#include "stdlib.h"
+#include "string.h"
+#include "pair_coul_dsf.h"
+#include "atom.h"
+#include "comm.h"
+#include "force.h"
+#include "neighbor.h"
+#include "neigh_list.h"
+#include "memory.h"
+#include "math_const.h"
+#include "error.h"
+
+using namespace LAMMPS_NS;
+using namespace MathConst;
+
+#define EWALD_F   1.12837917
+#define EWALD_P   0.3275911
+#define A1        0.254829592
+#define A2       -0.284496736
+#define A3        1.421413741
+#define A4       -1.453152027
+#define A5        1.061405429
+
+/* ---------------------------------------------------------------------- */
+
+PairCoulDSF::PairCoulDSF(LAMMPS *lmp) : Pair(lmp) {}
+
+/* ---------------------------------------------------------------------- */
+
+PairCoulDSF::~PairCoulDSF()
+{
+  if (allocated) {
+    memory->destroy(setflag);
+    memory->destroy(cutsq);
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+
+void PairCoulDSF::compute(int eflag, int vflag)
+{
+  int i,j,ii,jj,inum,jnum,itype,jtype;
+  double qtmp,xtmp,ytmp,ztmp,delx,dely,delz,ecoul,fpair;
+  double r,rsq,r2inv,forcecoul,factor_coul;
+  double prefactor,erfcc,erfcd,e_self,t;
+  int *ilist,*jlist,*numneigh,**firstneigh;
+  
+  ecoul = 0.0;
+  if (eflag || vflag) ev_setup(eflag,vflag);
+  else evflag = vflag_fdotr = 0;
+  
+  double **x = atom->x;
+  double **f = atom->f;
+  double *q = atom->q;
+  int *type = atom->type;
+  int nlocal = atom->nlocal;
+  double *special_coul = force->special_coul;
+  int newton_pair = force->newton_pair;
+  double qqrd2e = force->qqrd2e;
+
+  inum = list->inum;
+  ilist = list->ilist;
+  numneigh = list->numneigh;
+  firstneigh = list->firstneigh;
+  
+  // loop over neighbors of my atoms
+
+  for (ii = 0; ii < inum; ii++) {
+    i = ilist[ii];
+    qtmp = q[i];
+    xtmp = x[i][0];
+    ytmp = x[i][1];
+    ztmp = x[i][2];
+    itype = type[i];
+    jlist = firstneigh[i];
+    jnum = numneigh[i];
+    
+    if (evflag) {
+      e_self = -(e_shift/2.0 + alpha/MY_PIS) * qtmp*qtmp*qqrd2e;
+      ev_tally(i,i,nlocal,0,0.0,e_self,0.0,0.0,0.0,0.0);
+    }
+
+    for (jj = 0; jj < jnum; jj++) {
+      j = jlist[jj];
+      factor_coul = special_coul[sbmask(j)];
+      j &= NEIGHMASK;
+
+      delx = xtmp - x[j][0];
+      dely = ytmp - x[j][1];
+      delz = ztmp - x[j][2];
+      rsq = delx*delx + dely*dely + delz*delz;
+      jtype = type[j];
+
+      if (rsq < cutsq[itype][jtype]) {
+        r2inv = 1.0/rsq;
+
+        if (rsq < cut_coulsq) {
+          r = sqrt(rsq);
+          prefactor = factor_coul * qqrd2e*qtmp*q[j]/r;
+          erfcd = exp(-alpha*alpha*rsq);
+          t = 1.0 / (1.0 + EWALD_P*alpha*r);
+          erfcc = t * (A1+t*(A2+t*(A3+t*(A4+t*A5)))) * erfcd;
+          forcecoul = prefactor * (erfcc/r + 2.0*alpha/MY_PIS * erfcd + 
+            r*f_shift) * r;
+        }
+
+        fpair = forcecoul * r2inv;
+        f[i][0] += delx*fpair;
+        f[i][1] += dely*fpair;
+        f[i][2] += delz*fpair;
+        if (newton_pair || j < nlocal) {
+          f[j][0] -= delx*fpair;
+          f[j][1] -= dely*fpair;
+          f[j][2] -= delz*fpair;
+        }
+
+        if (eflag) {
+          if (rsq < cut_coulsq) {
+            ecoul = prefactor * (erfcc - r*e_shift - rsq*f_shift);
+          } else ecoul = 0.0;
+        }
+
+        if (evflag) ev_tally(i,j,nlocal,newton_pair,
+                             0.0,ecoul,fpair,delx,dely,delz);
+      }
+    }
+  }
+
+  if (vflag_fdotr) virial_fdotr_compute();
+}
+
+/* ----------------------------------------------------------------------
+   allocate all arrays
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::allocate()
+{
+  allocated = 1;
+  int n = atom->ntypes;
+
+  memory->create(setflag,n+1,n+1,"pair:setflag");
+  for (int i = 1; i <= n; i++)
+    for (int j = i; j <= n; j++)
+      setflag[i][j] = 0;
+
+  memory->create(cutsq,n+1,n+1,"pair:cutsq");
+}
+
+/* ----------------------------------------------------------------------
+   global settings
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::settings(int narg, char **arg)
+{
+  if (narg != 2) error->all(FLERR,"Illegal pair_style command");
+
+  alpha = force->numeric(arg[0]);
+  cut_coul = force->numeric(arg[1]);
+}
+
+/* ----------------------------------------------------------------------
+   set coeffs for one or more type pairs
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::coeff(int narg, char **arg)
+{
+  if (narg != 2) error->all(FLERR,"Incorrect args for pair coefficients");
+  if (!allocated) allocate();
+
+  int ilo,ihi,jlo,jhi;
+  force->bounds(arg[0],atom->ntypes,ilo,ihi);
+  force->bounds(arg[1],atom->ntypes,jlo,jhi);
+  
+  int count = 0;
+  for (int i = ilo; i <= ihi; i++) {
+    for (int j = MAX(jlo,i); j <= jhi; j++) {
+      setflag[i][j] = 1;
+      count++;
+    }
+  }
+
+  if (count == 0) error->all(FLERR,"Incorrect args for pair coefficients");
+}
+
+/* ----------------------------------------------------------------------
+   init specific to this pair style
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::init_style()
+{
+  if (!atom->q_flag)
+    error->all(FLERR,"Pair style coul/dsf requires atom attribute q");
+
+  neighbor->request(this);
+
+  cut_coulsq = cut_coul * cut_coul;
+  double erfcc = erfc(alpha*cut_coul); 
+  double erfcd = exp(-alpha*alpha*cut_coul*cut_coul);
+  f_shift = -(erfcc/cut_coulsq + 2.0/MY_PIS*alpha*erfcd/cut_coul); 
+  e_shift = erfcc/cut_coul - f_shift*cut_coul; 
+}
+
+/* ----------------------------------------------------------------------
+   init for one type pair i,j and corresponding j,i
+------------------------------------------------------------------------- */
+
+double PairCoulDSF::init_one(int i, int j)
+{
+  return cut_coul;
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 writes to restart file
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::write_restart(FILE *fp)
+{
+  write_restart_settings(fp);
+
+  int i,j;
+  for (i = 1; i <= atom->ntypes; i++)
+    for (j = i; j <= atom->ntypes; j++) {
+      fwrite(&setflag[i][j],sizeof(int),1,fp);
+    }
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 reads from restart file, bcasts
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::read_restart(FILE *fp)
+{
+  read_restart_settings(fp);
+  allocate();
+
+  int i,j;
+  int me = comm->me;
+  for (i = 1; i <= atom->ntypes; i++)
+    for (j = i; j <= atom->ntypes; j++) {
+      if (me == 0) fread(&setflag[i][j],sizeof(int),1,fp);
+      MPI_Bcast(&setflag[i][j],1,MPI_INT,0,world);
+    }
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 writes to restart file
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::write_restart_settings(FILE *fp)
+{
+  fwrite(&alpha,sizeof(double),1,fp);
+  fwrite(&cut_coul,sizeof(double),1,fp);
+  fwrite(&offset_flag,sizeof(int),1,fp);
+  fwrite(&mix_flag,sizeof(int),1,fp);
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 reads from restart file, bcasts
+------------------------------------------------------------------------- */
+
+void PairCoulDSF::read_restart_settings(FILE *fp)
+{
+  if (comm->me == 0) {
+    fread(&alpha,sizeof(double),1,fp);
+    fread(&cut_coul,sizeof(double),1,fp);
+    fread(&offset_flag,sizeof(int),1,fp);
+    fread(&mix_flag,sizeof(int),1,fp);
+  }
+  MPI_Bcast(&alpha,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&cut_coul,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&offset_flag,1,MPI_INT,0,world);
+  MPI_Bcast(&mix_flag,1,MPI_INT,0,world);
+}
+
+/* ---------------------------------------------------------------------- */
+
+double PairCoulDSF::single(int i, int j, int itype, int jtype, double rsq,
+                           double factor_coul, double factor_lj,
+                           double &fforce)
+{
+  double r2inv,r6inv,r,erfcc,erfcd,prefactor,t;
+  double forcecoul,phicoul,philj;
+  
+  r2inv = 1.0/rsq;
+
+  if (rsq < cut_coulsq) {
+    r = sqrt(rsq);
+    prefactor = factor_coul * force->qqrd2e * atom->q[i]*atom->q[j]/r;
+    erfcd = exp(-alpha*alpha*rsq);
+    t = 1.0 / (1.0 + EWALD_P*alpha*r);
+    erfcc = t * (A1+t*(A2+t*(A3+t*(A4+t*A5)))) * erfcd;
+	
+    forcecoul = prefactor * (erfcc/r + 2.0*alpha/MY_PIS*erfcd + 
+      r*f_shift) * r;
+  } else forcecoul = 0.0;
+  
+  fforce = forcecoul * r2inv;
+      
+  double eng = 0.0;
+  if (r < cut_coulsq) { 
+    phicoul = prefactor * (erfcc - r*e_shift - rsq*f_shift);
+    eng += phicoul;
+  } 
+  
+  return eng;
+}
+
+/* ---------------------------------------------------------------------- */
+
+void *PairCoulDSF::extract(char *str, int &dim)
+{
+  if (strcmp(str,"cut_coul") == 0) {
+    dim = 0;
+    return (void *) &cut_coul;
+  }
+  return NULL;
+}
diff --git a/src/pair_coul_dsf.h b/src/pair_coul_dsf.h
new file mode 100644
index 0000000000..6a89e622c3
--- /dev/null
+++ b/src/pair_coul_dsf.h
@@ -0,0 +1,62 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under 
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+#ifdef PAIR_CLASS
+
+PairStyle(coul/dsf,PairCoulDSF)
+
+#else
+
+#ifndef LMP_PAIR_COUL_DSF_H
+#define LMP_PAIR_COUL_DSF_H
+
+#include "pair.h"
+
+namespace LAMMPS_NS {
+
+class PairCoulDSF : public Pair {
+ public:
+  PairCoulDSF(class LAMMPS *);
+  ~PairCoulDSF();
+  void compute(int, int);
+  void settings(int, char **);
+  void coeff(int, char **);
+  void init_style();
+  double init_one(int, int);
+  void write_restart(FILE *);
+  void read_restart(FILE *);
+  void write_restart_settings(FILE *);
+  void read_restart_settings(FILE *);
+  double single(int, int, int, int, double, double, double, double &);
+  void *extract(char *, int &);
+
+ protected:
+  double cut_coul,cut_coulsq;
+  double alpha;
+  double f_shift,e_shift;
+  
+  void allocate();
+};
+
+}
+
+#endif
+#endif
+
+/* ERROR/WARNING messages:
+
+E: Pair style coul/dsf requires atom attribute q
+
+The atom style defined does not have this attribute.
+
+*/
diff --git a/src/pair_lj_cut_coul_dsf.cpp b/src/pair_lj_cut_coul_dsf.cpp
new file mode 100644
index 0000000000..796eb7465a
--- /dev/null
+++ b/src/pair_lj_cut_coul_dsf.cpp
@@ -0,0 +1,470 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under 
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+/* ----------------------------------------------------------------------
+   Contributing author: Trung Dac Nguyen (ORNL)
+   References: Fennell and Gezelter, JCP 124, 234104 (2006)
+------------------------------------------------------------------------- */
+
+#include "math.h"
+#include "stdio.h"
+#include "stdlib.h"
+#include "string.h"
+#include "pair_lj_cut_coul_dsf.h"
+#include "atom.h"
+#include "comm.h"
+#include "force.h"
+#include "neighbor.h"
+#include "neigh_list.h"
+#include "memory.h"
+#include "math_const.h"
+#include "error.h"
+
+using namespace LAMMPS_NS;
+using namespace MathConst;
+
+#define EWALD_F   1.12837917
+#define EWALD_P   0.3275911
+#define A1        0.254829592
+#define A2       -0.284496736
+#define A3        1.421413741
+#define A4       -1.453152027
+#define A5        1.061405429
+
+/* ---------------------------------------------------------------------- */
+
+PairLJCutCoulDSF::PairLJCutCoulDSF(LAMMPS *lmp) : Pair(lmp) {}
+
+/* ---------------------------------------------------------------------- */
+
+PairLJCutCoulDSF::~PairLJCutCoulDSF()
+{
+  if (allocated) {
+    memory->destroy(setflag);
+    memory->destroy(cutsq);
+
+    memory->destroy(cut_lj);
+    memory->destroy(cut_ljsq);
+    memory->destroy(epsilon);
+    memory->destroy(sigma);
+    memory->destroy(lj1);
+    memory->destroy(lj2);
+    memory->destroy(lj3);
+    memory->destroy(lj4);
+    memory->destroy(offset);
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::compute(int eflag, int vflag)
+{
+  int i,j,ii,jj,inum,jnum,itype,jtype;
+  double qtmp,xtmp,ytmp,ztmp,delx,dely,delz,evdwl,ecoul,fpair;
+  double r,rsq,r2inv,r6inv,forcecoul,forcelj,factor_coul,factor_lj;
+  double prefactor,erfcc,erfcd,e_self,t;
+  int *ilist,*jlist,*numneigh,**firstneigh;
+  
+  evdwl = ecoul = 0.0;
+  if (eflag || vflag) ev_setup(eflag,vflag);
+  else evflag = vflag_fdotr = 0;
+  
+  double **x = atom->x;
+  double **f = atom->f;
+  double *q = atom->q;
+  int *type = atom->type;
+  int nlocal = atom->nlocal;
+  double *special_coul = force->special_coul;
+  double *special_lj = force->special_lj;
+  int newton_pair = force->newton_pair;
+  double qqrd2e = force->qqrd2e;
+
+  inum = list->inum;
+  ilist = list->ilist;
+  numneigh = list->numneigh;
+  firstneigh = list->firstneigh;
+  
+  // loop over neighbors of my atoms
+
+  for (ii = 0; ii < inum; ii++) {
+    i = ilist[ii];
+    qtmp = q[i];
+    xtmp = x[i][0];
+    ytmp = x[i][1];
+    ztmp = x[i][2];
+    itype = type[i];
+    jlist = firstneigh[i];
+    jnum = numneigh[i];
+    
+    if (evflag) {
+      e_self = -(e_shift/2.0 + alpha/MY_PIS) * qtmp*qtmp*qqrd2e;
+      ev_tally(i,i,nlocal,0,0.0,e_self,0.0,0.0,0.0,0.0);
+    }
+
+    for (jj = 0; jj < jnum; jj++) {
+      j = jlist[jj];
+      factor_lj = special_lj[sbmask(j)];
+      factor_coul = special_coul[sbmask(j)];
+      j &= NEIGHMASK;
+
+      delx = xtmp - x[j][0];
+      dely = ytmp - x[j][1];
+      delz = ztmp - x[j][2];
+      rsq = delx*delx + dely*dely + delz*delz;
+      jtype = type[j];
+
+      if (rsq < cutsq[itype][jtype]) {
+        r2inv = 1.0/rsq;
+
+        if (rsq < cut_ljsq[itype][jtype]) {
+          r6inv = r2inv*r2inv*r2inv;
+          forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
+        } else forcelj = 0.0;
+
+        if (rsq < cut_coulsq) {
+          r = sqrt(rsq);
+          prefactor = factor_coul * qqrd2e*qtmp*q[j]/r;
+          erfcd = exp(-alpha*alpha*r*r);
+          t = 1.0 / (1.0 + EWALD_P*alpha*r);
+          erfcc = t * (A1+t*(A2+t*(A3+t*(A4+t*A5)))) * erfcd;
+          forcecoul = prefactor * (erfcc/r + 2.0*alpha/MY_PIS * erfcd + 
+            r*f_shift) * r;
+        }
+
+        fpair = (forcecoul + factor_lj*forcelj) * r2inv;
+        f[i][0] += delx*fpair;
+        f[i][1] += dely*fpair;
+        f[i][2] += delz*fpair;
+        if (newton_pair || j < nlocal) {
+          f[j][0] -= delx*fpair;
+          f[j][1] -= dely*fpair;
+          f[j][2] -= delz*fpair;
+        }
+
+        if (eflag) {
+          if (rsq < cut_ljsq[itype][jtype]) {
+            evdwl = r6inv*(lj3[itype][jtype]*r6inv-lj4[itype][jtype]) -
+                    offset[itype][jtype];
+            evdwl *= factor_lj;
+          } else evdwl = 0.0;
+          
+          if (rsq < cut_coulsq) {
+            ecoul = prefactor * (erfcc - r*e_shift - rsq*f_shift);
+          } else ecoul = 0.0;
+        }
+
+        if (evflag) ev_tally(i,j,nlocal,newton_pair,
+                             evdwl,ecoul,fpair,delx,dely,delz);
+      }
+    }
+  }
+
+  if (vflag_fdotr) virial_fdotr_compute();
+}
+
+/* ----------------------------------------------------------------------
+   allocate all arrays
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::allocate()
+{
+  allocated = 1;
+  int n = atom->ntypes;
+
+  memory->create(setflag,n+1,n+1,"pair:setflag");
+  for (int i = 1; i <= n; i++)
+    for (int j = i; j <= n; j++)
+      setflag[i][j] = 0;
+
+  memory->create(cutsq,n+1,n+1,"pair:cutsq");
+
+  memory->create(cut_lj,n+1,n+1,"pair:cut_lj");
+  memory->create(cut_ljsq,n+1,n+1,"pair:cut_ljsq");
+  memory->create(epsilon,n+1,n+1,"pair:epsilon");
+  memory->create(sigma,n+1,n+1,"pair:sigma");
+  memory->create(lj1,n+1,n+1,"pair:lj1");
+  memory->create(lj2,n+1,n+1,"pair:lj2");
+  memory->create(lj3,n+1,n+1,"pair:lj3");
+  memory->create(lj4,n+1,n+1,"pair:lj4");
+  memory->create(offset,n+1,n+1,"pair:offset");
+}
+
+/* ----------------------------------------------------------------------
+   global settings
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::settings(int narg, char **arg)
+{
+  if (narg != 3) error->all(FLERR,"Illegal pair_style command");
+
+  alpha = force->numeric(arg[0]);
+  cut_lj_global = force->numeric(arg[1]);
+  cut_coul = force->numeric(arg[2]);
+  
+  // reset cutoffs that have been explicitly set
+
+  if (allocated) {
+    int i,j;
+    for (i = 1; i <= atom->ntypes; i++)
+      for (j = i+1; j <= atom->ntypes; j++)
+        if (setflag[i][j])
+          cut_lj[i][j] = cut_lj_global;
+  }
+}
+
+/* ----------------------------------------------------------------------
+   set coeffs for one or more type pairs
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::coeff(int narg, char **arg)
+{
+  if (narg < 4 || narg > 5) 
+    error->all(FLERR,"Incorrect args for pair coefficients");
+  if (!allocated) allocate();
+
+  int ilo,ihi,jlo,jhi;
+  force->bounds(arg[0],atom->ntypes,ilo,ihi);
+  force->bounds(arg[1],atom->ntypes,jlo,jhi);
+  
+  double epsilon_one = force->numeric(arg[2]);
+  double sigma_one = force->numeric(arg[3]);
+
+  double cut_lj_one = cut_lj_global;
+  if (narg == 5) cut_lj_one = force->numeric(arg[4]);
+    
+  int count = 0;
+  for (int i = ilo; i <= ihi; i++) {
+    for (int j = MAX(jlo,i); j <= jhi; j++) {
+      epsilon[i][j] = epsilon_one;
+      sigma[i][j] = sigma_one;
+      cut_lj[i][j] = cut_lj_one;
+      setflag[i][j] = 1;
+      count++;
+    }
+  }
+
+  if (count == 0) error->all(FLERR,"Incorrect args for pair coefficients");
+}
+
+/* ----------------------------------------------------------------------
+   init specific to this pair style
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::init_style()
+{
+  if (!atom->q_flag)
+    error->all(FLERR,"Pair style lj/cut/coul/dsf requires atom attribute q");
+
+  neighbor->request(this);
+
+  cut_coulsq = cut_coul * cut_coul;
+  double erfcc = erfc(alpha*cut_coul); 
+  double erfcd = exp(-alpha*alpha*cut_coul*cut_coul);
+  f_shift = -(erfcc/cut_coulsq + 2.0/MY_PIS*alpha*erfcd/cut_coul); 
+  e_shift = erfcc/cut_coul - f_shift*cut_coul; 
+}
+
+/* ----------------------------------------------------------------------
+   init for one type pair i,j and corresponding j,i
+------------------------------------------------------------------------- */
+
+double PairLJCutCoulDSF::init_one(int i, int j)
+{
+  if (setflag[i][j] == 0) {
+    epsilon[i][j] = mix_energy(epsilon[i][i],epsilon[j][j],
+                               sigma[i][i],sigma[j][j]);
+    sigma[i][j] = mix_distance(sigma[i][i],sigma[j][j]);
+    cut_lj[i][j] = mix_distance(cut_lj[i][i],cut_lj[j][j]);
+  }
+
+  double cut = MAX(cut_lj[i][j],cut_coul);
+  cut_ljsq[i][j] = cut_lj[i][j] * cut_lj[i][j];
+  
+  lj1[i][j] = 48.0 * epsilon[i][j] * pow(sigma[i][j],12.0);
+  lj2[i][j] = 24.0 * epsilon[i][j] * pow(sigma[i][j],6.0);
+  lj3[i][j] = 4.0 * epsilon[i][j] * pow(sigma[i][j],12.0);
+  lj4[i][j] = 4.0 * epsilon[i][j] * pow(sigma[i][j],6.0);
+     
+  if (offset_flag) {
+    double ratio = sigma[i][j] / cut_lj[i][j];
+    offset[i][j] = 4.0 * epsilon[i][j] * (pow(ratio,12.0) - pow(ratio,6.0));
+  } else offset[i][j] = 0.0;
+  
+  cut_ljsq[j][i] = cut_ljsq[i][j];
+  lj1[j][i] = lj1[i][j];
+  lj2[j][i] = lj2[i][j];
+  lj3[j][i] = lj3[i][j];
+  lj4[j][i] = lj4[i][j];
+  offset[j][i] = offset[i][j];
+
+  // compute I,J contribution to long-range tail correction
+  // count total # of atoms of type I and J via Allreduce
+
+  if (tail_flag) {
+    int *type = atom->type;
+    int nlocal = atom->nlocal;
+
+    double count[2],all[2];
+    count[0] = count[1] = 0.0;
+    for (int k = 0; k < nlocal; k++) {
+      if (type[k] == i) count[0] += 1.0;
+      if (type[k] == j) count[1] += 1.0;
+    }
+    MPI_Allreduce(count,all,2,MPI_DOUBLE,MPI_SUM,world);
+        
+    double sig2 = sigma[i][j]*sigma[i][j];
+    double sig6 = sig2*sig2*sig2;
+    double rc3 = cut_lj[i][j]*cut_lj[i][j]*cut_lj[i][j];
+    double rc6 = rc3*rc3;
+    double rc9 = rc3*rc6;
+    etail_ij = 8.0*MY_PI*all[0]*all[1]*epsilon[i][j] * 
+               sig6 * (sig6 - 3.0*rc6) / (9.0*rc9); 
+    ptail_ij = 16.0*MY_PI*all[0]*all[1]*epsilon[i][j] * 
+               sig6 * (2.0*sig6 - 3.0*rc6) / (9.0*rc9); 
+  } 
+
+  return cut;
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 writes to restart file
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::write_restart(FILE *fp)
+{
+  write_restart_settings(fp);
+
+  int i,j;
+  for (i = 1; i <= atom->ntypes; i++)
+    for (j = i; j <= atom->ntypes; j++) {
+      fwrite(&setflag[i][j],sizeof(int),1,fp);
+      if (setflag[i][j]) {
+        fwrite(&epsilon[i][j],sizeof(double),1,fp);
+        fwrite(&sigma[i][j],sizeof(double),1,fp);
+        fwrite(&cut_lj[i][j],sizeof(double),1,fp);
+	    }
+    }
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 reads from restart file, bcasts
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::read_restart(FILE *fp)
+{
+  read_restart_settings(fp);
+  allocate();
+
+  int i,j;
+  int me = comm->me;
+  for (i = 1; i <= atom->ntypes; i++)
+    for (j = i; j <= atom->ntypes; j++) {
+      if (me == 0) fread(&setflag[i][j],sizeof(int),1,fp);
+      MPI_Bcast(&setflag[i][j],1,MPI_INT,0,world);
+      if (setflag[i][j]) {
+        if (me == 0) {
+          fread(&epsilon[i][j],sizeof(double),1,fp);
+          fread(&sigma[i][j],sizeof(double),1,fp);
+          fread(&cut_lj[i][j],sizeof(double),1,fp);
+        }
+        MPI_Bcast(&epsilon[i][j],1,MPI_DOUBLE,0,world);
+        MPI_Bcast(&sigma[i][j],1,MPI_DOUBLE,0,world);
+        MPI_Bcast(&cut_lj[i][j],1,MPI_DOUBLE,0,world);
+      }
+    }
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 writes to restart file
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::write_restart_settings(FILE *fp)
+{
+  fwrite(&alpha,sizeof(double),1,fp);
+  fwrite(&cut_lj_global,sizeof(double),1,fp);
+  fwrite(&cut_coul,sizeof(double),1,fp);
+  fwrite(&offset_flag,sizeof(int),1,fp);
+  fwrite(&mix_flag,sizeof(int),1,fp);
+}
+
+/* ----------------------------------------------------------------------
+  proc 0 reads from restart file, bcasts
+------------------------------------------------------------------------- */
+
+void PairLJCutCoulDSF::read_restart_settings(FILE *fp)
+{
+  if (comm->me == 0) {
+    fread(&alpha,sizeof(double),1,fp);
+    fread(&cut_lj_global,sizeof(double),1,fp);
+    fread(&cut_coul,sizeof(double),1,fp);
+    fread(&offset_flag,sizeof(int),1,fp);
+    fread(&mix_flag,sizeof(int),1,fp);
+  }
+  MPI_Bcast(&alpha,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&cut_lj_global,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&cut_coul,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&offset_flag,1,MPI_INT,0,world);
+  MPI_Bcast(&mix_flag,1,MPI_INT,0,world);
+}
+
+/* ---------------------------------------------------------------------- */
+
+double PairLJCutCoulDSF::single(int i, int j, int itype, int jtype, double rsq,
+                                double factor_coul, double factor_lj,
+                                double &fforce)
+{
+  double r2inv,r6inv,r,erfcc,erfcd,prefactor;
+  double forcecoul,forcelj,phicoul,philj;
+  
+  r2inv = 1.0/rsq;
+  if (rsq < cut_ljsq[itype][jtype]) {
+    r6inv = r2inv*r2inv*r2inv;
+    forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
+  } else forcelj = 0.0;
+
+  if (rsq < cut_coulsq) {
+    r = sqrt(rsq);
+    prefactor = factor_coul * force->qqrd2e * atom->q[i]*atom->q[j]/r;
+    erfcc = erfc(alpha*r); 
+    erfcd = exp(-alpha*alpha*r*r);
+    forcecoul = prefactor * (erfcc/r + 2.0*alpha/MY_PIS * erfcd + 
+      r*f_shift) * r;
+  } else forcecoul = 0.0;
+  
+  fforce = (forcecoul + factor_lj*forcelj) * r2inv;
+      
+  double eng = 0.0;
+  if (rsq < cut_ljsq[itype][jtype]) {
+    philj = r6inv*(lj3[itype][jtype]*r6inv-lj4[itype][jtype]) -
+      offset[itype][jtype];
+    eng += factor_lj*philj;
+  }
+
+  if (r < cut_coulsq) { 
+    phicoul = prefactor * (erfcc - r*e_shift - rsq*f_shift);
+    eng += phicoul;
+  } 
+  
+  return eng;
+}
+
+/* ---------------------------------------------------------------------- */
+
+void *PairLJCutCoulDSF::extract(char *str, int &dim)
+{
+  if (strcmp(str,"cut_coul") == 0) {
+    dim = 0;
+    return (void *) &cut_coul;
+  }
+  return NULL;
+}
diff --git a/src/pair_lj_cut_coul_dsf.h b/src/pair_lj_cut_coul_dsf.h
new file mode 100644
index 0000000000..73b1bd8b81
--- /dev/null
+++ b/src/pair_lj_cut_coul_dsf.h
@@ -0,0 +1,59 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under 
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+#ifdef PAIR_CLASS
+
+PairStyle(lj/cut/coul/dsf,PairLJCutCoulDSF)
+
+#else
+
+#ifndef LMP_PAIR_LJ_CUT_COUL_DSF_H
+#define LMP_PAIR_LJ_CUT_COUL_DSF_H
+
+#include "pair.h"
+
+namespace LAMMPS_NS {
+
+class PairLJCutCoulDSF : public Pair {
+ public:
+  PairLJCutCoulDSF(class LAMMPS *);
+  ~PairLJCutCoulDSF();
+  void compute(int, int);
+  void settings(int, char **);
+  void coeff(int, char **);
+  void init_style();
+  double init_one(int, int);
+  void write_restart(FILE *);
+  void read_restart(FILE *);
+  void write_restart_settings(FILE *);
+  void read_restart_settings(FILE *);
+  double single(int, int, int, int, double, double, double, double &);
+  void *extract(char *, int &);
+
+ protected:
+  double cut_lj_global;
+  double **cut_lj,**cut_ljsq;
+  double **epsilon,**sigma;
+  double **lj1,**lj2,**lj3,**lj4,**offset;
+  
+  double cut_coul,cut_coulsq;
+  double alpha;
+  double f_shift,e_shift;
+  
+  void allocate();
+};
+
+}
+
+#endif
+#endif