double precision  gcart, gxcart, gradcag,gradxag
      common /mdgrad/ gcart(3,0:MAXRES), gxcart(3,0:MAXRES),
     & gradcag(3,MAXRES),gradxag(3,MAXRES)
       integer dimen,dimen1, dimen3, ifrag(2,50,maxprocs/20), 
     &                       ipair(2,100,maxprocs/20),iset,
     &                       mset(maxprocs/20),nset
       double precision IP,ISC(ntyp+1),mp,
     & msc(ntyp+1),d_t_work(MAXRES6),
     & d_t_work_new(MAXRES6),d_t(3,0:MAXRES2),d_t_new(3,0:MAXRES2),
     & d_af_work(MAXRES6),d_as_work(MAXRES6),
     & d_t_old(3,0:MAXRES2),d_a_old(3,0:MAXRES2),d_a_short(3,0:MAXRES2),
     & Gmat(MAXRES2,MAXRES2),Ginv(MAXRES2,MAXRES2),A(MAXRES2,MAXRES2),
     & d_a(3,0:MAXRES2),d_a_work(6*MAXRES),kinetic_force(MAXRES6),
     & Gsqrp(MAXRES2,MAXRES2),Gsqrm(MAXRES2,MAXRES2),
     & vtot(MAXRES2),Gvec(maxres2,maxres2),Geigen(maxres2)
       double precision v_ini,d_time,d_time0,t_bath,tau_bath,
     & EK,potE,potEcomp(0:n_ene+4),totE,totT,amax,kinetic_T,dvmax,damax,
     & edriftmax,
     & eq_time,wfrag(50,maxprocs/20),wpair(100,maxprocs/20),
     & qfrag(50),qpair(100),
     & qinfrag(50,maxprocs/20),qinpair(100,maxprocs/20),
     & Ucdfrag,Ucdpair,dUdconst(3,0:MAXRES),Uconst,
     & dUdxconst(3,0:MAXRES),dqwol(3,0:MAXRES),dxqwol(3,0:MAXRES),
     & utheta(maxfrag_back),ugamma(maxfrag_back),uscdiff(maxfrag_back),
     & dutheta(maxres),dugamma(maxres),duscdiff(3,maxres),
     & duscdiffx(3,maxres),wfrag_back(3,maxfrag_back,maxprocs/20),
     & uconst_back
      integer n_timestep,ntwx,ntwe,lang,count_reset_moment,
     & count_reset_vel,reset_fricmat,nfrag,npair,nfrag_back,
     & ifrag_back(3,maxfrag_back,maxprocs/20),ntime_split,ntime_split0,
     & maxtime_split
      integer nresn,nyosh,nnos,hremd
      double precision glogs,qmass,vlogs,xlogs
      logical large,print_compon,tbf,rest,reset_moment,reset_vel,
     & surfarea,rattle,usampl,mdpdb,RESPA,tnp,tnp1,tnh,xiresp
      integer igmult_start,igmult_end,my_ng_count,ng_start,ng_counts,
     & nginv_start,nginv_counts,myginv_ng_count
      common /back_constr/ uconst_back,utheta,ugamma,uscdiff,
     & dutheta,dugamma,duscdiff,duscdiffx,
     & wfrag_back,nfrag_back,ifrag_back
      common /qmeas/ qfrag,qpair,qinfrag,qinpair,wfrag,wpair,eq_time,
     & Ucdfrag,Ucdpair,dUdconst,dUdxconst,dqwol,dxqwol,Uconst,
     & iset,mset,nset,usampl,ifrag,ipair,npair,nfrag
      common /mdpar/ v_ini,d_time,d_time0,scal_fric,
     & t_bath,tau_bath,dvmax,damax,n_timestep,mdpdb,
     & ntime_split,ntime_split0,maxtime_split,
     & ntwx,ntwe,large,print_compon,tbf,rest,tnp,tnp1,tnh,hremd
      common /MDcalc/ totT,totE,potE,potEcomp,EK,amax,edriftmax,
     & kinetic_T
      common /lagrange/ d_t,d_t_old,d_t_new,d_t_work,
     & d_t_work_new,d_a,d_a_old,d_a_work,d_af_work,d_as_work,d_a_short,
     & kinetic_force,
     & A,Ginv,Gmat,Gvec,Geigen,Gsqrp,Gsqrm,
     & vtot,dimen,dimen1,dimen3,lang,
     & reset_moment,reset_vel,count_reset_moment,count_reset_vel,
     & rattle,RESPA
      common /inertia/ IP,ISC,MP,MSC
      double precision scal_fric,rwat,etawat,gamp,
     & gamsc(ntyp),stdfp,stdfsc(ntyp),stdforcp(MAXRES),
     & stdforcsc(MAXRES),pstok,restok(ntyp+1),cPoise,Rb
      common /langevin/ pstok,restok,gamp,gamsc,
     & stdfp,stdfsc,stdforcp,stdforcsc,rwat,etawat,cPoise,Rb,surfarea,
     & reset_fricmat
      common /mdpmpi/ igmult_start,igmult_end,my_ng_count,
     & myginv_ng_count,
     & ng_start(0:MaxProcs-1),ng_counts(0:MaxProcs-1),
     & nginv_start(0:MaxProcs),nginv_counts(0:MaxProcs-1)
      double precision pi_np,pistar,s_np,s12_np,Q_np,E_old,H0,E_long,
     & sold_np,d_t_half,Csplit
      common /nosepoincare/ pi_np,pistar,s_np,s12_np,Q_np,E_old,H0,
     & E_long,sold_np,d_t_half(3,0:MAXRES2),Csplit
      common /nosehoover/ glogs(maxmnh),qmass(maxmnh),
     &                    vlogs(maxmnh),xlogs(maxmnh),
     &                    nresn,nyosh,nnos,xiresp