int i;
t_ho_params hop;
t_lj_params ljp;
+ t_tersoff_params tp;
double s,e;
memset(moldyn,0,sizeof(t_moldyn));
moldyn->mwrite=atoi(argv[++i]);
strncpy(moldyn->mfb,argv[++i],64);
break;
- case 'D':
- moldyn->dwrite=atoi(argv[++i]);
- strncpy(moldyn->dfb,argv[++i],64);
- break;
case 'S':
moldyn->swrite=atoi(argv[++i]);
strncpy(moldyn->sfb,argv[++i],64);
if(moldyn->swrite)
moldyn->lvstat|=MOLDYN_LVSTAT_SAVE;
- if(moldyn->dwrite) {
- moldyn->dfd=open(moldyn->dfb,O_WRONLY|O_CREAT|O_TRUNC);
- if(moldyn->dfd<0) {
- perror("[moldyn] dfd open");
- return moldyn->dfd;
- }
- write(moldyn->dfd,moldyn,sizeof(t_moldyn));
- moldyn->lvstat|=MOLDYN_LVSTAT_DUMP;
- }
-
if((moldyn->vwrite)&&(vis)) {
moldyn->visual=vis;
visual_init(vis,moldyn->vfb);
return 0;
}
-int create_lattice(unsigned char type,int element,double mass,double lc,
+int create_lattice(u8 type,int element,double mass,double lc,
int a,int b,int c,t_atom **atom) {
int count;
for(i=0;i<lc->cells;i++)
//list_init(&(lc->subcell[i]),1);
- list_init(&(lc->subcell[i]),lc->listfd);
+ list_init(&(lc->subcell[i]));
link_cell_update(moldyn);
ny=lc->ny;
nz=lc->nz;
- for(i=0;i<nx*ny*nz;i++)
+ for(i=0;i<lc->cells;i++)
list_destroy(&(moldyn->lc.subcell[i]));
- for(count=0;count<moldyn->count;count++) {
- i=atom[count].r.x/lc->x;
- j=atom[count].r.y/lc->y;
- k=atom[count].r.z/lc->z;
+ for(count=0;count<moedyn->count;count++) {
+ i=(atom[count].r.x+(moldyn->dim.x/2))/lc->x;
+ j=(atom[count].r.y+(moldyn->dim.y/2))/lc->y;
+ k=(atom[count].r.z+(moldyn->dim.z/2))/lc->z;
list_add_immediate_ptr(&(moldyn->lc.subcell[i+j*nx+k*nx*ny]),
&(atom[count]));
}
int ci,cj,ck;
int nx,ny,nz;
int x,y,z;
- unsigned char bx,by,bz;
+ u8 bx,by,bz;
lc=&(moldyn->lc);
nx=lc->nx;
count2=27;
a=nx*ny;
+
cell[0]=lc->subcell[i+j*nx+k*a];
for(ci=-1;ci<=1;ci++) {
bx=0;
z=(z+nz)%nz;
bz=1;
}
- if(!(x|y|z)) continue;
+ if(!(ci|cj|ck)) continue;
if(bx|by|bz) {
cell[--count2]=lc->subcell[x+y*nx+z*a];
}
}
}
+ lc->dnlc=count2;
+ lc->countn=27;
+
return count2;
}
int fd;
char fb[128];
+ /* initialize linked cell method */
+ link_cell_init(moldyn);
+
/* logging & visualization */
e=moldyn->ewrite;
m=moldyn->mwrite;
moldyn->potential_force_function(moldyn);
for(i=0;i<moldyn->time_steps;i++) {
- /* show runs */
- printf(".");
-
- /* neighbour list update */
- link_cell_update(moldyn);
/* integration step */
moldyn->integrate(moldyn);
write(fd,moldyn->atom,
moldyn->count*sizeof(t_atom));
}
+ close(fd);
}
}
- if(d) {
- if(!(i%d))
- write(moldyn->dfd,moldyn->atom,
- moldyn->count*sizeof(t_atom));
-
- }
if(v) {
- if(!(i%v))
+ if(!(i%v)) {
visual_atoms(moldyn->visual,i*moldyn->tau,
moldyn->atom,moldyn->count);
+ printf("\rsteps: %d",i);
+ fflush(stdout);
+ }
}
}
v3_add(&(atom[i].v),&(atom[i].v),&delta);
}
+ /* neighbour list update */
+printf("list update ...\n");
+ link_cell_update(moldyn);
+printf("done\n");
+
/* forces depending on chosen potential */
- moldyn->potential_force_function(moldyn);
+printf("calc potential/force ...\n");
+ potential_force_calc(moldyn);
+ //moldyn->potential_force_function(moldyn);
+printf("done\n");
for(i=0;i<count;i++) {
/* again velocities */
*
*/
-/* harmonic oscillator potential and force */
+/* generic potential and force calculation */
-int harmonic_oscillator(t_moldyn *moldyn) {
+int potential_force_calc(t_moldyn *moldyn) {
- t_ho_params *params;
- t_atom *atom,*btom;
+ int i,count;
+ t_atom *atom;
t_linkcell *lc;
- t_list *this,neighbour[27];
- int i,j,c;
- int count;
- t_3dvec force,distance;
- double d,u;
- double sc,equi_dist;
- int ni,nj,nk;
+ t_list neighbour[27];
+ t_list *this;
+ double u;
+ u8 bc,bc3;
+ int countn,dnlc;
- params=moldyn->pot_params;
+ count=moldyn->count;
atom=moldyn->atom;
lc=&(moldyn->lc);
- sc=params->spring_constant;
- equi_dist=params->equilibrium_distance;
- count=moldyn->count;
- u=0.0;
+ /* reset energy */
+ moldyn->energy=0.0;
+
for(i=0;i<count;i++) {
- /* determine cell + neighbours */
- ni=atom[i].r.x/lc->x;
- nj=atom[i].r.y/lc->y;
- nk=atom[i].r.z/lc->z;
- c=link_cell_neighbour_index(moldyn,ni,nj,nk,neighbour);
-
- /* processing cell of atom i */
- this=&(neighbour[0]);
- list_reset(this); /* list has 1 element at minimum */
- do {
- btom=this->current->data;
- if(btom==&(atom[i]))
- continue;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- d=v3_norm(&distance);
- u+=(0.5*sc*(d-equi_dist)*(d-equi_dist));
- v3_scale(&force,&distance,-sc*(1.0-(equi_dist/d)));
- v3_add(&(atom[i].f),&(atom[i].f),&force);
- } while(list_next(this)!=L_NO_NEXT_ELEMENT);
+
+ /* reset force */
+ v3_zero(&(atom[i].f));
- /* neighbours not doing boundary condition overflow */
- for(j=1;j<c;j++) {
- this=&(neighbour[j]);
- list_reset(this); /* there might not be a single atom */
- if(this->start!=NULL) {
+ /* single particle potential/force */
+ if(atom[i].attr&ATOM_ATTR_1BP)
+ moldyn->pf_func1b(moldyn,&(atom[i]));
- do {
- btom=this->current->data;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- d=v3_norm(&distance);
- if(d<=moldyn->cutoff) {
- u+=(0.5*sc*(d-equi_dist)*(d-equi_dist));
- v3_scale(&force,&distance,
- -sc*(1.0-(equi_dist/d)));
- v3_add(&(atom[i].f),&(atom[i].f),
- &force);
- }
- } while(list_next(this)!=L_NO_NEXT_ELEMENT);
+ /* 2 body pair potential/force */
+ if(atom[i].attr&(ATOM_ATTR_2BP|ATOM_ATTR_3BP)) {
+
+ link_cell_neighbour_index(moldyn,
+ (atom[i].r.x+moldyn->dim.x/2)/lc->x,
+ (atom[i].r.y+moldyn->dim.y/2)/lc->y,
+ (atom[i].r.z+moldyn->dim.z/2)/lc->z,
+ neighbour);
- }
- }
+ countn=lc->countn;
+ dnlc=lc->dnlc;
- /* neighbours due to boundary conditions */
- for(j=c;j<27;j++) {
- this=&(neighbour[j]);
- list_reset(this); /* check boundary conditions */
- if(this->start!=NULL) {
+ for(j=0;j<countn;j++) {
- do {
- btom=this->current->data;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- v3_per_bound(&distance,&(moldyn->dim));
- d=v3_norm(&distance);
- if(d<=moldyn->cutoff) {
- u+=(0.5*sc*(d-equi_dist)*(d-equi_dist));
- v3_scale(&force,&distance,
- -sc*(1.0-(equi_dist/d)));
- v3_add(&(atom[i].f),&(atom[i].f),
- &force);
- }
- } while(list_next(this)!=L_NO_NEXT_ELEMENT);
+ this=&(neighbour[j]);
+ list_reset(this);
+
+ if(this->start==NULL)
+ continue;
+
+ bc=(j<dnlc)?0:1;
+
+ do {
+ btom=this->current->data;
+
+ if(btom==&(atom[i]))
+ continue;
+
+ if((btom->attr&ATOM_ATTR_2BP)&
+ (atom[i].attr&ATOM_ATTR_2BP))
+ moldyn->pf_func2b(moldyn,
+ &(atom[i]),
+ btom,
+ bc);
+ /* 3 body potential/force */
+
+ if(!(atom[i].attr&ATOM_ATTR_3BP)||
+ !(btom->attr&ATOM_ATTR_3BP))
+ continue;
+
+ link_cell_neighbour_index(moldyn,
+ (btom->r.x+moldyn->dim.x/2)/lc->x,
+ (btom->r.y+moldyn->dim.y/2)/lc->y,
+ (btom->r.z+moldyn->dim.z/2)/lc->z,
+ neighbourk);
+
+ for(k=0;k<lc->countn;k++) {
+
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+
+ if(thisk->start==NULL)
+ continue;
+
+ bck=(k<lc->dnlc)?0:1;
+
+ do {
+
+ ktom=thisk->current->data;
+
+ if(!(ktom->attr&ATOM_ATTR_3BP))
+ continue;
+
+ if(ktom==btom)
+ continue;
+
+ if(ktom==&(atom[i]))
+ continue;
+
+ moldyn->pf_func3b(moldyn,&(atom[i]),btom,ktom,bck);
+
+ } while(list_next(thisk)!=\
+ L_NO_NEXT_ELEMENT);
+
+ } while(list_next(this)!=L_NO_NEXT_ELEMENT);
}
}
}
- moldyn->energy=u;
+ return 0;
+}
+
+/*
+ * periodic boundayr checking
+ */
+
+int check_per_bound(t_moldyn *moldyn,t_3dvec *a) {
+
+ double x,y,z;
+
+ x=0.5*dim->x;
+ y=0.5*dim->y;
+ z=0.5*dim->z;
+
+ if(moldyn->MOLDYN_ATTR_PBX)
+ if(a->x>=x) a->x-=dim->x;
+ else if(-a->x>x) a->x+=dim->x;
+ if(moldyn->MOLDYN_ATTR_PBY)
+ if(a->y>=y) a->y-=dim->y;
+ else if(-a->y>y) a->y+=dim->y;
+ if(moldyn->MOLDYN_ATTR_PBZ)
+ if(a->z>=z) a->z-=dim->z;
+ else if(-a->z>z) a->z+=dim->z;
+
+ return 0;
+}
+
+
+/*
+ * example potentials
+ */
+
+/* harmonic oscillator potential and force */
+
+int harmonic_oscillator(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc)) {
+
+ t_ho_params *params;
+ t_3dvec force,distance;
+ double d;
+ double sc,equi_dist;
+
+ params=moldyn->pot2b_params;
+ sc=params->spring_constant;
+ equi_dist=params->equilibrium_distance;
+
+ v3_sub(&distance,&(ai->r),&(aj->r);
+
+ v3_per_bound(&distance,&(moldyn->dim));
+ if(bc) check_per_bound(moldyn,&distance);
+ d=v3_norm(&distance);
+ if(d<=moldyn->cutoff) {
+ /* energy is 1/2 (d-d0)^2, but we will add this twice ... */
+ moldyn->energy+=(0.25*sc*(d-equi_dist)*(d-equi_dist));
+ v3_scale(&force,&distance,-sc*(1.0-(equi_dist/d)));
+ v3_add(&(ai->f),&(ai->f),&force);
+ }
return 0;
}
/* lennard jones potential & force for one sort of atoms */
-int lennard_jones(t_moldyn *moldyn) {
+int lennard_jones(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
t_lj_params *params;
- t_atom *atom,*btom;
- t_linkcell *lc;
- t_list *this,neighbour[27];
- int i,j,c;
- int count;
t_3dvec force,distance;
double d,h1,h2,u;
double eps,sig6,sig12;
- int ni,nj,nk;
params=moldyn->pot_params;
- atom=moldyn->atom;
- lc=&(moldyn->lc);
- count=moldyn->count;
eps=params->epsilon4;
sig6=params->sigma6;
sig12=params->sigma12;
- u=0.0;
- for(i=0;i<count;i++) {
- /* determine cell + neighbours */
- ni=atom[i].r.x/lc->x;
- nj=atom[i].r.y/lc->y;
- nk=atom[i].r.z/lc->z;
- c=link_cell_neighbour_index(moldyn,ni,nj,nk,neighbour);
-
- /* processing cell of atom i */
- this=&(neighbour[0]);
- list_reset(this); /* list has 1 element at minimum */
- do {
- btom=this->current->data;
- if(btom==&(atom[i]))
- continue;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- d=1.0/v3_absolute_square(&distance); /* 1/r^2 */
- h1=d*d; /* 1/r^4 */
- h2*=d; /* 1/r^6 */
- h1=h2*h2; /* 1/r^12 */
- u+=eps*(sig12*h1-sig6*h2);
- h2*=d; /* 1/r^8 */
- h1*=d; /* 1/r^14 */
- h2*=6*sig6;
- h1*=12*sig12;
- d=-h1+h2;
- d*=eps;
- v3_scale(&force,&distance,d);
- v3_add(&(atom[i].f),&(atom[i].f),&force);
+ v3_sub(&distance,&(ai->r),&(aj->r));
+ if(bc) check_per_bound(moldyn,&distance);
+ d=v3_absolute_square(&distance); /* 1/r^2 */
+ if(d<=moldyn->cutoff_square) {
+ d=1.0/d; /* 1/r^2 */
+ h2=d*d; /* 1/r^4 */
+ h2*=d; /* 1/r^6 */
+ h1=h2*h2; /* 1/r^12 */
+ /* energy is eps*..., but we will add this twice ... */
+ moldyn->energy+=0.5*eps*(sig12*h1-sig6*h2);
+ h2*=d; /* 1/r^8 */
+ h1*=d; /* 1/r^14 */
+ h2*=6*sig6;
+ h1*=12*sig12;
+ d=+h1-h2;
+ d*=eps;
+ v3_scale(&force,&distance,d);
+ v3_add(&(ai->f),&(aj->f),&force);
+ }
+
+ return 0;
+}
+
+/*
+ * tersoff potential & force for 2 sorts of atoms
+ */
+
+/* tersoff 2 body part */
+
+int tersoff_2bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
+
+ t_tersoff_params *params;
+ t_3dvec dist_ij;
+ double d_ij;
+
+ params=moldyn->pot_params;
+
+ /*
+ * we need: f_c, df_c, f_r, df_r
+ *
+ * therefore we need: R, S
+ */
+
+ v3_sub(&dist_ij,&(ai->r),&(aj->r));
+
+ if(bc) check_per_bound(moldyn,&dist_ij);
+
+ if(ai->bnum==aj->bnum) {
+ S=params->S[ai->bnum];
+ R=params->R[ai->bnum];
+ }
+ else {
+ S=params->Smixed;
+ R=params->Rmixed;
+ }
+
+ d_ij=v3_norm(&dist_ij);
+
+ if(d_ij<=S) {
+ f_r=A*exp(-lamda*d_ij);
+ df_r=-lambda*f_r/d_ij;
+ if(d_ij<R) {
+ /* f_c = 1, df_c = 0 */
+ v3_scale(&force,&dist_ij,df_r);
+ }
+ else {
+ s_r=S-R;
+ arg=PI*(d_ij-R)/s_r;
+ f_c=0.5+0.5*cos(arg);
+ df_c=-0.5*sin(arg)*(PI/(s_r*d_ij));
+ scale=df_c*f_r+df_r*f_c;
+ v3_scale(&force,&dist_ij,scale);
+ v3_add(&(ai->f),&(ai->f),&force);
+ }
+ moldyn->energy+=(f_r*f_c);
+ }
+
+ return 0;
+}
+
+/* tersoff 3 body part */
+
+int tersoff(t_moldyn *moldyn,t_atom *ai,t_atom *aj,t_atom *ak,u8 bc,u8 bck) {
+
+ t_tersoff_params *params;
+ t_3dvec dist_ij;
+ double d_ij;
+
+ params=moldyn->pot_params;
+
+ /* 2 body part of the tersoff potential */
+
+ v3_sub(&dist_ij,&(ai->r),&(aj->r));
+ if(bc) check_per_bound(moldyn,&dist_ij);
+ d_ij=v3_norm(&dist_ij);
+ if(d_ij<=S) {
+
+ /* determine the tersoff parameters */
+ if(atom[i].element!=btom->element) {
+ S=sqrt(TERSOFF_S[e1]*TERSOFF_S[e2]);
+ R=R_m;
+ A=;
+ lambda=;
+ B=;
+ mu=;
+ chi=;
+ beta=;
+ betaN=;
+
+ if(d_ij<=R) {
+ df_r=-lambda*A*exp(-lambda*d_ij)/d_ij;
+ v3_scale(&force,&dist_ij,df_r);
+ v3_add(&(atom[i].f),&(atom[i].f),
+ &force);
+ }
+ else {
+ s_r=S-R;
+ arg1=PI*(d_ij-R)/s_r;
+ f_c=0.5+0.5*cos(arg1);
+ df_c=-0.5*sin(arg1)*(PI/(s_r*d_ij));
+ f_r=A*exp(-lambda*d_ij);
+ df_r=-lambda*f_r/d_ij;
+ scale=df_c*f_r+df_r*f_c;
+ v3_scale(&force,&dist_ij,scale);
+ v3_add(&(atom[i].f),&(atom[i].f),
+ &force);
+ }
+ }
+ else
+ continue;
+
+
+ /* end 2 body stuff */
+
+ /* determine cell neighbours of btom */
+ ki=(btom->r.x+(moldyn->dim.x/2))/lc->x;
+ kj=(btom->r.y+(moldyn->dim.y/2))/lc->y;
+ kk=(btom->r.z+(moldyn->dim.z/2))/lc->z;
+ ck=link_cell_neighbour_index(moldyn,ki,kj,kk,
+ neighbourk);
+
+ /* go for zeta - 3 body stuff! */
+ zeta=0.0;
+ d_ij2=d_ij*d_ij;
+
+ /* cell of btom */
+ thisk=&(neighbourk[0]);
+ list_reset(thisk);
+ do {
+ ktom=thisk->current->data;
+ if(ktom==btom)
+ continue;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (1) */
+
+ v3_sub(&dist_ik,ktom,&(atom[i]));
+ d_ik=v3_norm(&dist_ik);
+ if(d_ik<=Sik) {
+
+ Rik=;
+ Sik=;
+ Aik=;
+ lambda_ik=;
+ Bik=;
+ mu_ik=;
+ omega_ik=;
+ c_i=;
+ d_i=;
+ h_i=;
+
+
+ if(d_ik<=Rik) {
+ f_cik=1.0;
+ df_cik=0.0;
+ }
+ else {
+ sik_rik=Sik-Rik;
+ arg1ik=PI*(d_ik-Rik)/sik_rik;
+ f_cik=0.5+0.5*cos(arg1ik);
+ df_cik=-0.5*sin(arg1ik)* \
+ (PI/(sik_rik*d_ik));
+ f_rik=Aik*exp(-lambda_ik*d_ik);
+ f_aik=-Bik*exp(-mu_ik*d_ik);
+ }
+
+ v3_sub(&distance_jk,ktom,btom);
+ cos_theta=(d_ij2+d_ik*d_ik-d_jk*d_jk)/\
+ (2*d_ij*d_ik);
+ sin_theta=sqrt(1.0/\
+ (cos_theta*cos_theta));
+ theta=arccos(cos_theta);
+
+
+ }
+ else
+ continue;
+
+ /* end 3 body stuff (1) */
+
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ /* direct neighbours of btom cell */
+ for(k=1;k<ck;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (2) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ }
+ }
+
+ /* indirect neighbours of btom cell */
+ for(k=ck;k<27;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ }
+ }
+
+
} while(list_next(this)!=L_NO_NEXT_ELEMENT);
- /* neighbours not doing boundary condition overflow */
+ /*
+ * direct neighbour cells of atom i
+ */
for(j=1;j<c;j++) {
this=&(neighbour[j]);
- list_reset(this); /* there might not be a single atom */
+ list_reset(this);
if(this->start!=NULL) {
do {
btom=this->current->data;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- d=v3_absolute_square(&distance); /* r^2 */
- if(d<=moldyn->cutoff_square) {
- d=1.0/d; /* 1/r^2 */
- h1=d*d; /* 1/r^4 */
- h2*=d; /* 1/r^6 */
- h1=h2*h2; /* 1/r^12 */
- u+=eps*(sig12*h1-sig6*h2);
- h2*=d; /* 1/r^8 */
- h1*=d; /* 1/r^14 */
- h2*=6*sig6;
- h1*=12*sig12;
- d=-h1+h2;
- d*=eps;
- v3_scale(&force,&distance,d);
- v3_add(&(atom[i].f),&(atom[i].f),
- &force);
+
+ /* 2 body stuff */
+
+
+ /* determine cell neighbours of btom */
+ ki=(btom->r.x+(moldyn->dim.x/2))/lc->x;
+ kj=(btom->r.y+(moldyn->dim.y/2))/lc->y;
+ kk=(btom->r.z+(moldyn->dim.z/2))/lc->z;
+ ck=link_cell_neighbour_index(moldyn,ki,kj,kk,
+ neighbourk);
+
+ /* cell of btom */
+ thisk=&(neighbourk[0]);
+ list_reset(thisk);
+ do {
+ ktom=thisk->current->data;
+ if(ktom==btom)
+ continue;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (1) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ /* direct neighbours of btom cell */
+ for(k=1;k<ck;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (2) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
}
+ }
+
+ /* indirect neighbours of btom cell */
+ for(k=ck;k<27;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (3) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ }
+ }
+
+
} while(list_next(this)!=L_NO_NEXT_ELEMENT);
-
+
}
}
- /* neighbours due to boundary conditions */
+ /*
+ * indirect neighbour cells of atom i
+ */
for(j=c;j<27;j++) {
this=&(neighbour[j]);
- list_reset(this); /* check boundary conditions */
+ list_reset(this);
if(this->start!=NULL) {
do {
btom=this->current->data;
- v3_sub(&distance,&(atom[i].r),&(btom->r));
- v3_per_bound(&distance,&(moldyn->dim));
- d=v3_absolute_square(&distance); /* r^2 */
- if(d<=moldyn->cutoff_square) {
- d=1.0/d; /* 1/r^2 */
- h1=d*d; /* 1/r^4 */
- h2*=d; /* 1/r^6 */
- h1=h2*h2; /* 1/r^12 */
- u+=eps*(sig12*h1-sig6*h2);
- h2*=d; /* 1/r^8 */
- h1*=d; /* 1/r^14 */
- h2*=6*sig6;
- h1*=12*sig12;
- d=-h1+h2;
- d*=eps;
- v3_scale(&force,&distance,d);
- v3_add(&(atom[i].f),&(atom[i].f),
- &force);
+
+ /* 2 body stuff */
+
+
+ /* determine cell neighbours of btom */
+ ki=(btom->r.x+(moldyn->dim.x/2))/lc->x;
+ kj=(btom->r.y+(moldyn->dim.y/2))/lc->y;
+ kk=(btom->r.z+(moldyn->dim.z/2))/lc->z;
+ ck=link_cell_neighbour_index(moldyn,ki,kj,kk,
+ neighbourk);
+
+ /* cell of btom */
+ thisk=&(neighbourk[0]);
+ list_reset(thisk);
+ do {
+ ktom=thisk->current->data;
+ if(ktom==btom)
+ continue;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (1) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ /* direct neighbours of btom cell */
+ for(k=1;k<ck;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (2) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
}
+ }
+
+ /* indirect neighbours of btom cell */
+ for(k=ck;k<27;k++) {
+ thisk=&(neighbourk[k]);
+ list_reset(thisk);
+ if(thisk->start!=NULL) {
+
+ do {
+ ktom=thisk->current->data;
+ if(ktom==&(atom[i]))
+ continue;
+
+ /* 3 body stuff (3) */
+
+ } while(list_next(thisk)!=L_NO_NEXT_ELEMENT);
+
+ }
+ }
+
+
} while(list_next(this)!=L_NO_NEXT_ELEMENT);
}
}
+
}
- moldyn->energy=u;
-
+ moldyn->energy=0.5*u;
+
return 0;
}
projects / physik / posic.git / blobdiff