X-Git-Url: https://www.hackdaworld.org/gitweb/?a=blobdiff_plain;f=moldyn.c;h=94d596e91878237cf41a127cd8aa947cbcd18997;hb=fb951c04e522e4637618bf622fc67194c2a7b15f;hp=9db5cd9053fea64ce0cc5bd09cc667caa360bd4a;hpb=9f6af2cd82a72451741b68ca333f94c6c1d2eec5;p=physik%2Fposic.git

diff --git a/moldyn.c b/moldyn.c
index 9db5cd9..94d596e 100644
--- a/moldyn.c
+++ b/moldyn.c
@@ -121,12 +121,15 @@ int set_dim(t_moldyn *moldyn,double x,double y,double z,u8 visualize) {
 		moldyn->vis.dim.z=z;
 	}
 
+	moldyn->dv=0.0001*moldyn->volume;
+
 	printf("[moldyn] dimensions in A and A^3 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?"yes":"no");
+	printf("  delta volume (pressure calc): %f\n",moldyn->dv);
 
 	return 0;
 }
@@ -279,6 +282,7 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
 	count=moldyn->count;
 
 	/* how many atoms do we expect */
+	if(type==CUBIC) new*=1;
 	if(type==FCC) new*=4;
 	if(type==DIAMOND) new*=8;
 
@@ -294,6 +298,9 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
 	v3_zero(&origin);
 
 	switch(type) {
+		case CUBIC:
+			ret=cubic_init(a,b,c,atom,&origin);
+			break;
 		case FCC:
 			ret=fcc_init(a,b,c,lc,atom,&origin);
 			break;
@@ -329,6 +336,15 @@ int create_lattice(t_moldyn *moldyn,u8 type,double lc,int element,double mass,
 	return ret;
 }
 
+/* cubic init */
+int cubic_init(int a,int b,int c,double lc,t_atom *atom,t_3dvec *origin) {
+
+	int count;
+	t_3dvec r
+
+HIER WEITER !
+}
+
 /* fcc lattice init */
 int fcc_init(int a,int b,int c,double lc,t_atom *atom,t_3dvec *origin) {
 
@@ -507,6 +523,7 @@ double temperature_calc(t_moldyn *moldyn) {
 
 	atom=moldyn->atom;
 
+	double_ekin=0;
 	for(i=0;i<moldyn->count;i++)
 		double_ekin+=atom[i].mass*v3_absolute_square(&(atom[i].v));
 
@@ -577,34 +594,153 @@ int scale_velocity(t_moldyn *moldyn,u8 equi_init) {
 	return 0;
 }
 
+double ideal_gas_law_pressure(t_moldyn *moldyn) {
+
+	double p;
+
+	p=moldyn->count*moldyn->t*K_BOLTZMANN/moldyn->volume;
+printf("temp = %f => ideal gas law pressure: %f\n",moldyn->t,p/ATM);
+
+	return p;
+}
+
 double pressure_calc(t_moldyn *moldyn) {
 
 	int i;
-	t_atom *atom;
-	double p1,p2,p=0;
-	
-	for(i=0;i<moldyn->count;i++) {
-		
+	double p1,p;
+	double v,h;
+	t_virial *virial;
 
+	v=0.0;
+	for(i=0;i<moldyn->count;i++) {
+		virial=&(moldyn->atom[i].virial);
+		v+=(virial->xx+virial->yy+virial->zz);
 	}
 
+	h=moldyn->count*K_BOLTZMANN*moldyn->t;
+
+	p=(h-ONE_THIRD*v);
+	p/=moldyn->volume;
+
 	p1=(moldyn->count*K_BOLTZMANN*moldyn->t-ONE_THIRD*moldyn->vt1);
 	p1/=moldyn->volume;
 
-	p2=(moldyn->count*K_BOLTZMANN*moldyn->t-ONE_THIRD*moldyn->vt2);
-	p2/=moldyn->volume;
+	printf("debug: vt1=%f v=%f nkt=%f\n",moldyn->vt1,v,h);
 
-	printf("compare pressures: %f %f\n",p1/ATM,p2/ATM);
+	printf("compare pressures: %f %f %f\n",p1/ATM,p/ATM,h/moldyn->volume/ATM);
 
 	return moldyn->p;
 }	
 
+double thermodynamic_pressure_calc(t_moldyn *moldyn) {
+
+	t_3dvec dim,*tp;
+	double u,p;
+	double scale;
+	t_atom *store;
+
+	tp=&(moldyn->tp);
+	store=malloc(moldyn->count*sizeof(t_atom));
+	if(store==NULL) {
+		printf("[moldyn] allocating store mem failed\n");
+		return -1;
+	}
+
+	/* save unscaled potential energy + atom/dim configuration */
+	u=moldyn->energy;
+	memcpy(store,moldyn->atom,moldyn->count*sizeof(t_atom));
+	dim=moldyn->dim;
+
+	/* derivative with respect to x direction */
+	scale=1.0+moldyn->dv/(moldyn->dim.y*moldyn->dim.z);
+	scale_dim(moldyn,scale,TRUE,0,0);
+	scale_atoms(moldyn,scale,TRUE,0,0);
+	potential_force_calc(moldyn);
+	tp->x=(moldyn->energy-u)/moldyn->dv;
+	p=tp->x*tp->x;
+
+	/* restore atomic configuration + dim */
+	memcpy(moldyn->atom,store,moldyn->count*sizeof(t_atom));
+	moldyn->dim=dim;
+
+	/* derivative with respect to y direction */
+	scale=1.0+moldyn->dv/(moldyn->dim.x*moldyn->dim.z);
+	scale_dim(moldyn,scale,0,TRUE,0);
+	scale_atoms(moldyn,scale,0,TRUE,0);
+	potential_force_calc(moldyn);
+	tp->y=(moldyn->energy-u)/moldyn->dv;
+	p+=tp->y*tp->y;
+
+	/* restore atomic configuration + dim */
+	memcpy(moldyn->atom,store,moldyn->count*sizeof(t_atom));
+	moldyn->dim=dim;
+
+	/* derivative with respect to z direction */
+	scale=1.0+moldyn->dv/(moldyn->dim.x*moldyn->dim.y);
+	scale_dim(moldyn,scale,0,0,TRUE);
+	scale_atoms(moldyn,scale,0,0,TRUE);
+	potential_force_calc(moldyn);
+	tp->z=(moldyn->energy-u)/moldyn->dv;
+	p+=tp->z*tp->z;
+
+	/* restore atomic configuration + dim */
+	memcpy(moldyn->atom,store,moldyn->count*sizeof(t_atom));
+	moldyn->dim=dim;
+
+	printf("dU/dV komp addiert = %f\n",(tp->x+tp->y+tp->z)/ATM);
+
+	scale=1.0+pow(moldyn->dv/moldyn->volume,ONE_THIRD);
+
+	scale_dim(moldyn,scale,1,1,1);
+	scale_dim(moldyn,scale,1,1,1);
+	potential_force_calc(moldyn);
+
+	printf("dU/dV einfach = %f\n",(moldyn->energy-u)/moldyn->dv/ATM);
+
+	/* restore atomic configuration + dim */
+	memcpy(moldyn->atom,store,moldyn->count*sizeof(t_atom));
+	moldyn->dim=dim;
+
+	/* restore energy */
+	moldyn->energy=u;
+
+	return sqrt(p);
+}
+
 double get_pressure(t_moldyn *moldyn) {
 
 	return moldyn->p;
 
 }
 
+int scale_dim(t_moldyn *moldyn,double scale,u8 x,u8 y,u8 z) {
+
+	t_3dvec *dim;
+
+	dim=&(moldyn->dim);
+
+	if(x) dim->x*=scale;
+	if(y) dim->y*=scale;
+	if(z) dim->z*=scale;
+
+	return 0;
+}
+
+int scale_atoms(t_moldyn *moldyn,double scale,u8 x,u8 y,u8 z) {
+
+	int i;
+	t_3dvec *r;
+
+	for(i=0;i<moldyn->count;i++) {
+		r=&(moldyn->atom[i].r);
+		if(x) r->x*=scale;
+		if(y) r->y*=scale;
+		if(z) r->z*=scale;
+	}
+
+	return 0;
+}
+
 int scale_volume(t_moldyn *moldyn) {
 
 	t_atom *atom;
@@ -979,22 +1115,17 @@ int moldyn_integrate(t_moldyn *moldyn) {
 		if(moldyn->pt_scale&(P_SCALE_BERENDSEN|P_SCALE_DIRECT))
 			scale_volume(moldyn);
 
+printf("-> %f\n",thermodynamic_pressure_calc(moldyn)/ATM);
+
 		/* check for log & visualization */
-//double ax;
-//double ao;
-//double av;
 		if(e) {
 			if(!(i%e))
-//ao=sqrt(0.1/M_SI);
-//ax=((0.28-0.25)*sqrt(3)*LC_SI/2)*cos(ao*i);
-//av=ao*(0.28-0.25)*sqrt(3)*LC_SI/2*sin(ao*i);
 				update_e_kin(moldyn);
 				dprintf(moldyn->efd,
 				        "%f %f %f %f\n",
 				        moldyn->time,moldyn->ekin,
 				        moldyn->energy,
 				        get_total_energy(moldyn));
-//moldyn->atom[0].r.x,ax,av*av*M_SI,0.1*ax*ax,av*av*M_SI+0.1*ax*ax);
 		}
 		if(m) {
 			if(!(i%m)) {
@@ -1115,27 +1246,32 @@ int potential_force_calc(t_moldyn *moldyn) {
 	/* reset energy */
 	moldyn->energy=0.0;
 
-	moldyn->vt2=0.0;
-	
-	/* get energy and force of every atom */
+	/* reset virial */
+	moldyn->vt1=0.0;
+
+	/* reset force, site energy and virial of every atom */
 	for(i=0;i<count;i++) {
 
 		/* reset force */
 		v3_zero(&(itom[i].f));
 
-		/* reset viral of atom i */
-		virial=&(itom[i].virial);
+		/* reset virial */
+		virial=(&(itom[i].virial));
 		virial->xx=0.0;
 		virial->yy=0.0;
 		virial->zz=0.0;
 		virial->xy=0.0;
 		virial->xz=0.0;
 		virial->yz=0.0;
-		moldyn->vt1=0.0;
-
+	
 		/* reset site energy */
 		itom[i].e=0.0;
 
+	}
+
+	/* get energy,force and virial of every atom */
+	for(i=0;i<count;i++) {
+
 		/* single particle potential/force */
 		if(itom[i].attr&ATOM_ATTR_1BP)
 			moldyn->func1b(moldyn,&(itom[i]));
@@ -1241,13 +1377,9 @@ printf("\n\n");
 printf("\n\n");
 #endif
 
-	moldyn->vt2=0.0;
-	for(i=0;i<count;i++)
-		moldyn->vt2-=v3_scalar_product(&(itom[i].r),&(itom[i].f));
-
-//printf("compare: vt1: %f vt2: %f\n",moldyn->vt1,moldyn->vt2);
-
-//pressure_calc(moldyn);
+temperature_calc(moldyn);
+pressure_calc(moldyn);
+ideal_gas_law_pressure(moldyn);
 
 	return 0;
 }