basic p control added, virial still needed!
[physik/posic.git] / moldyn.c
index aaab0de..b6fa8d3 100644 (file)
--- a/moldyn.c
+++ b/moldyn.c
@@ -78,6 +78,13 @@ int set_temperature(t_moldyn *moldyn,double t_ref) {
        return 0;
 }
 
+int set_pressure(t_moldyn *moldyn,double p_ref) {
+
+       moldyn->p_ref=p_ref;
+
+       return 0;
+}
+
 int set_pt_scale(t_moldyn *moldyn,u8 ptype,double ptc,u8 ttype,double ttc) {
 
        moldyn->pt_scale=(ptype|ttype);
@@ -93,16 +100,19 @@ int set_dim(t_moldyn *moldyn,double x,double y,double z,u8 visualize) {
        moldyn->dim.y=y;
        moldyn->dim.z=z;
 
+       moldyn->volume=x*y*z;
+
        if(visualize) {
                moldyn->vis.dim.x=x;
                moldyn->vis.dim.y=y;
                moldyn->vis.dim.z=z;
        }
 
-       printf("[moldyn] dimensions in A:\n");
+       printf("[moldyn] dimensions in A and A^2 respectively:\n");
        printf("  x: %f\n",moldyn->dim.x);
        printf("  y: %f\n",moldyn->dim.y);
        printf("  z: %f\n",moldyn->dim.z);
+       printf("  volume: %f\n",moldyn->volume);
        printf("  visualize simulation box: %s\n",visualize?"on":"off");
 
        return 0;
@@ -236,10 +246,11 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
 
        count=a*b*c;
 
+       /* how many atoms do we expect */
        if(type==FCC) count*=4;
-
        if(type==DIAMOND) count*=8;
 
+       /* allocate space for atoms */
        moldyn->atom=malloc(count*sizeof(t_atom));
        if(moldyn->atom==NULL) {
                perror("malloc (atoms)");
@@ -262,9 +273,10 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
 
        /* debug */
        if(ret!=count) {
-               printf("ok, there is something wrong ...\n");
-               printf("calculated -> %d atoms\n",count);
-               printf("created -> %d atoms\n",ret);
+               printf("[moldyn] creating lattice failed\n");
+               printf("  amount of atoms\n");
+               printf("  - expected: %d\n",count);
+               printf("  - created: %d\n",ret);
                return -1;
        }
 
@@ -280,7 +292,6 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
                check_per_bound(moldyn,&(moldyn->atom[count].r));
        }
 
-
        return ret;
 }
 
@@ -389,7 +400,7 @@ int scale_velocity(t_moldyn *moldyn,u8 equi_init) {
                        count+=1;
                }
        }
-       if(count!=0) moldyn->t=(2.0*e)/(3.0*count*K_BOLTZMANN);
+       if(count!=0) moldyn->t=e/(1.5*count*K_BOLTZMANN);
        else return 0;  /* no atoms involved in scaling! */
        
        /* (temporary) hack for e,t = 0 */
@@ -422,6 +433,57 @@ int scale_velocity(t_moldyn *moldyn,u8 equi_init) {
        return 0;
 }
 
+int scale_volume(t_moldyn *moldyn) {
+
+       t_atom *atom;
+       t_3dvec *dim,*vdim;
+       double virial,scale;
+       t_linkcell *lc;
+       int i;
+
+       atom=moldyn->atom;
+       dim=&(moldyn->dim);
+       vdim=&(moldyn->vis.dim);
+       lc=&(moldyn->lc);
+
+       for(i=0;i<moldyn->count;i++)
+               virial+=v3_norm(&(atom[i].virial));
+
+printf("%f\n",virial);
+       /* get pressure from virial */
+       moldyn->p=moldyn->count*K_BOLTZMANN*moldyn->t-ONE_THIRD*virial;
+       moldyn->p/=moldyn->volume;
+printf("%f\n",moldyn->p/(ATM));
+
+       /* scale factor */
+       if(moldyn->pt_scale&P_SCALE_BERENDSEN)
+               scale=3*sqrt(1-(moldyn->p_ref-moldyn->p)/moldyn->p_tc);
+       else 
+               /* should actually never be used */
+               scale=pow(moldyn->p/moldyn->p_ref,1.0/3.0);
+
+printf("scale = %f\n",scale);
+       /* actual scaling */
+       dim->x*=scale;
+       dim->y*=scale;
+       dim->z*=scale;
+       if(vdim->x) vdim->x=dim->x;
+       if(vdim->y) vdim->y=dim->y;
+       if(vdim->z) vdim->z=dim->z;
+       moldyn->volume*=(scale*scale*scale);
+
+       /* check whether we need a new linkcell init */
+       if((dim->x/moldyn->cutoff!=lc->nx)||
+          (dim->y/moldyn->cutoff!=lc->ny)||
+          (dim->z/moldyn->cutoff!=lc->nx)) {
+               link_cell_shutdown(moldyn);
+               link_cell_init(moldyn);
+       }
+
+       return 0;
+
+}
+
 double get_e_kin(t_moldyn *moldyn) {
 
        int i;
@@ -723,6 +785,12 @@ int moldyn_integrate(t_moldyn *moldyn) {
                /* p/t scaling */
                if(moldyn->pt_scale&(T_SCALE_BERENDSEN|T_SCALE_DIRECT))
                        scale_velocity(moldyn,FALSE);
+               if(moldyn->pt_scale&(P_SCALE_BERENDSEN|P_SCALE_DIRECT))
+{
+printf("going to do p scale ...\n");
+                       scale_volume(moldyn);
+printf("done\n");
+}
 
                /* check for log & visualization */
                if(e) {
@@ -801,14 +869,16 @@ int velocity_verlet(t_moldyn *moldyn) {
                v3_add(&(atom[i].r),&(atom[i].r),&delta);
                v3_scale(&delta,&(atom[i].f),0.5*tau_square/atom[i].mass);
                v3_add(&(atom[i].r),&(atom[i].r),&delta);
+//if(i==5) printf("v: %f %f %f\n",atom[i].r.x,(atom[i].r.x+moldyn->dim.x/2)/moldyn->lc.x,2*atom[i].r.x/moldyn->dim.x);
                check_per_bound(moldyn,&(atom[i].r));
+//if(i==5) printf("n: %f %f %f\n",atom[i].r.x,(atom[i].r.x+moldyn->dim.x/2)/moldyn->lc.x,2*atom[i].r.x/moldyn->dim.x);
 
                /* velocities */
                v3_scale(&delta,&(atom[i].f),0.5*tau/atom[i].mass);
                v3_add(&(atom[i].v),&(atom[i].v),&delta);
        }
 
-moldyn_bc_check(moldyn);
+//moldyn_bc_check(moldyn);
        /* neighbour list update */
        link_cell_update(moldyn);
 
@@ -840,7 +910,6 @@ int potential_force_calc(t_moldyn *moldyn) {
        t_linkcell *lc;
        t_list neighbour_i[27];
        t_list neighbour_i2[27];
-       //t_list neighbour_j[27];
        t_list *this,*that;
        u8 bc_ij,bc_ik;
        int dnlc;
@@ -851,13 +920,16 @@ int potential_force_calc(t_moldyn *moldyn) {
 
        /* reset energy */
        moldyn->energy=0.0;
-
+       
        /* get energy and force of every atom */
        for(i=0;i<count;i++) {
 
                /* reset force */
                v3_zero(&(itom[i].f));
 
+               /* reset viral of atom i */
+               v3_zero(&(itom[i].virial));
+
                /* single particle potential/force */
                if(itom[i].attr&ATOM_ATTR_1BP)
                        moldyn->func1b(moldyn,&(itom[i]));
@@ -971,9 +1043,9 @@ int check_per_bound(t_moldyn *moldyn,t_3dvec *a) {
 
        dim=&(moldyn->dim);
 
-       x=0.5*dim->x;
-       y=0.5*dim->y;
-       z=0.5*dim->z;
+       x=dim->x/2;
+       y=dim->y/2;
+       z=dim->z/2;
 
        if(moldyn->status&MOLDYN_STAT_PBX) {
                if(a->x>=x) a->x-=dim->x;
@@ -1234,7 +1306,8 @@ int tersoff_mult_2bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
                s_r=S-R;
                arg=M_PI*(d_ij-R)/s_r;
                f_c=0.5+0.5*cos(arg);
-               df_c=-0.5*sin(arg)*(M_PI/(s_r*d_ij));
+               //df_c=-0.5*sin(arg)*(M_PI/(s_r*d_ij)); /* MARK! */
+               df_c=0.5*sin(arg)*(M_PI/(s_r*d_ij));
                /* two body contribution (ij, ji) */
                v3_scale(&force,&dist_ij,-df_c*f_r-df_r*f_c);
                /* tell 3bp that S > r > R */
@@ -1505,7 +1578,8 @@ int tersoff_mult_3bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
                        s_r=S-R;
                        arg=M_PI*(d_ik-R)/s_r;
                        f_c_ik=0.5+0.5*cos(arg);
-                       df_c_ik=-0.5*sin(arg)*(M_PI/(s_r*d_ik));
+                       //df_c_ik=-0.5*sin(arg)*(M_PI/(s_r*d_ik)); /* MARK */
+                       df_c_ik=0.5*sin(arg)*(M_PI/(s_r*d_ik));
 
                        /* zeta_ij */
                        exchange->zeta_ij+=f_c_ik*g;
@@ -1555,13 +1629,13 @@ int tersoff_mult_3bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
                c2d2=exchange->cj2dj2;
 
                /* cosine of theta_jik by scalaproduct */
-               rr=v3_scalar_product(&dist_ij,&dist_jk); /* times -1 */
+               rr=-v3_scalar_product(&dist_ij,&dist_jk); /* -1, as ij -> ji */
                dd=d_ij*d_jk;
                cos_theta=rr/dd;
 
                /* d_costheta */
-               d_costheta1=1.0/(d_jk*d_ij);
-               d_costheta2=cos_theta/(d_ij*d_ij); /* in fact -cos(), but ^ */
+               d_costheta1=1.0/dd;
+               d_costheta2=cos_theta/(d_ij*d_ij);
 
                /* some usefull values */
                h_cos=(h-cos_theta);
@@ -1577,6 +1651,9 @@ int tersoff_mult_3bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
                v3_add(&temp1,&temp1,&temp2);
                v3_scale(&temp1,&temp1,-2.0*frac*h_cos/d2_h_cos2); /* dg */
 
+               /* store dg in temp2 and use it for dVjk later */
+               v3_copy(&temp2,&temp1);
+
                /* f_c_jk + {d,}zeta contribution (df_c_jk = 0) */
                dzeta=&(exchange->dzeta_ji);
                if(d_jk<R) {
@@ -1598,7 +1675,7 @@ int tersoff_mult_3bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
                        /* zeta_ji */
                        exchange->zeta_ji+=f_c_jk*g;
 
-                       /* dzeta_ij */
+                       /* dzeta_ji */
                        v3_scale(&temp1,&temp1,f_c_jk);
                        v3_add(dzeta,dzeta,&temp1);
                }
@@ -1606,20 +1683,21 @@ int tersoff_mult_3bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
                /* dV_jk stuff | add force contribution on atom i immediately */
                if(exchange->d_ij_between_rs) {
                        zeta=f_c*g;
-                       v3_scale(&temp1,&temp1,f_c);
-                       v3_scale(&temp2,&dist_ij,df_c);
-                       v3_add(&temp1,&temp1,&temp2);
+                       v3_scale(&temp1,&temp2,f_c);
+                       v3_scale(&temp2,&dist_ij,df_c*g);
+                       v3_add(&temp2,&temp2,&temp1); /* -> dzeta_jk in temp2 */
                }
                else {
                        zeta=g;
-                       // dzeta_jk is simply dg, which is temp1
+                       // dzeta_jk is simply dg, which is stored in temp2
                }
                /* betajnj * zeta_jk ^ nj-1 */
                tmp=exchange->betajnj*pow(zeta,(n-1.0));
-               tmp=-chi/2.0*pow(1+tmp*zeta,-1.0/(2.0*n)-1)*tmp;
-               v3_scale(&temp1,&temp1,tmp*B*exp(-mu*d_jk)*f_c_jk*0.5);
-               v3_add(&(ai->f),&(ai->f),&temp1); /* -1 skipped in f_a calc ^ */
+               tmp=-chi/2.0*pow((1+tmp*zeta),(-1.0/(2.0*n)-1))*tmp;
+               v3_scale(&temp2,&temp2,tmp*B*exp(-mu*d_jk)*f_c_jk*0.5);
+               v3_add(&(ai->f),&(ai->f),&temp2); /* -1 skipped in f_a calc ^ */
                                                  /* scaled with 0.5 ^ */
+
        }
 
        return 0;
@@ -1635,20 +1713,44 @@ int moldyn_bc_check(t_moldyn *moldyn) {
        t_atom *atom;
        t_3dvec *dim;
        int i;
+double x;
+u8 byte;
+int j,k;
 
        atom=moldyn->atom;
        dim=&(moldyn->dim);
+x=dim->x/2;
 
        for(i=0;i<moldyn->count;i++) {
-               if(atom[i].r.x>=dim->x/2||-atom[i].r.x>dim->x/2)
+               if(atom[i].r.x>=dim->x/2||-atom[i].r.x>dim->x/2) {
                        printf("FATAL: atom %d: x: %.20f (%.20f)\n",
-                              i,atom[i].r.x*1e10,dim->x/2*1e10);
+                              i,atom[i].r.x,dim->x/2);
+                       printf("diagnostic:\n");
+                       printf("-----------\natom.r.x:\n");
+                       for(j=0;j<8;j++) {
+                               memcpy(&byte,(u8 *)(&(atom[i].r.x))+j,1);
+                               for(k=0;k<8;k++)
+                                       printf("%d%c",
+                                       ((byte)&(1<<k))?1:0,
+                                       (k==7)?'\n':'|');
+                       }
+                       printf("---------------\nx=dim.x/2:\n");
+                       for(j=0;j<8;j++) {
+                               memcpy(&byte,(u8 *)(&x)+j,1);
+                               for(k=0;k<8;k++)
+                                       printf("%d%c",
+                                       ((byte)&(1<<k))?1:0,
+                                       (k==7)?'\n':'|');
+                       }
+                       if(atom[i].r.x==x) printf("the same!\n");
+                       else printf("different!\n");
+               }
                if(atom[i].r.y>=dim->y/2||-atom[i].r.y>dim->y/2)
                        printf("FATAL: atom %d: y: %.20f (%.20f)\n",
-                              i,atom[i].r.y*1e10,dim->y/2*1e10);
+                              i,atom[i].r.y,dim->y/2);
                if(atom[i].r.z>=dim->z/2||-atom[i].r.z>dim->z/2)
                        printf("FATAL: atom %d: z: %.20f (%.20f)\n",
-                              i,atom[i].r.z*1e10,dim->z/2*1e10);
+                              i,atom[i].r.z,dim->z/2);
        }
 
        return 0;