2 * posic.c - precipitation process of silicon carbide in silicon
4 * author: Frank Zirkelbach <hackbard@hackdaworld.org>
10 #include "init/init.h"
11 #include "visual/visual.h"
15 int main(int argc,char **argv) {
33 char fb[32]="saves/fcc_test";
37 rand_init(&random,NULL,1);
38 random.status|=RAND_STAT_VERBOSE;
40 /* testing random numbers */
41 //for(a=0;a<1000000;a++)
42 // printf("%f %f\n",rand_get_gauss(&random),
43 // rand_get_gauss(&random));
53 printf("placing silicon atoms ... ");
54 count=create_lattice(DIAMOND,Si,M_SI,LC_SI,a,b,c,&si);
55 printf("(%d) ok!\n",count);
57 printf("setting thermal fluctuations\n");
58 thermal_init(si,&random,count,t);
62 visual_atoms(&vis,0.0,si,count);
64 /* check kinetic energy */
66 e=get_e_kin(si,count);
67 printf("kinetic energy: %f\n",e);
68 printf("3/2 N k T = %f\n",1.5*count*K_BOLTZMANN*t);
70 /* check total momentum */
71 p=get_total_p(si,count);
72 printf("total momentum: %f\n",v3_norm(&p));
74 /* check potential energy */
77 md.potential=potential_lennard_jones;
82 lj.sigma6=3.0/16.0*LC_SI*LC_SI;
83 help=lj.sigma6*lj.sigma6;
85 lj.sigma12=lj.sigma6*lj.sigma6;
90 printf("potential energy: %f\n",u);
91 printf("total energy (1): %f\n",e+u);
92 printf("total energy (2): %f\n",get_total_energy(&md));
99 * let's do the actual md algorithm now
101 * integration of newtons equations
111 //printf("starting velocity verlet: ");
114 //for(runs=0;runs<RUNS;runs++) {
119 * r(t+h) = r(t) + h * dr/dt|t + h^2/2m * F(t)
120 * dr/dt|(t+h) = dr/dt|t + h/2m * (F(t) + F(t+h))
123 //for(i=0;i<amount_si;i++) {
124 // /* calculation of new positions r(t+h) */
125 // si[i].x+=si[i].vx*tau;
126 // si[i].y+=si[i].vy*tau;
127 // si[i].z+=si[i].vz*tau;
128 // si[i].x+=(tau2*si[i].fx/m2);
129 // if(si[i].x>LX) si[i].x-=LEN_X;
130 // else if(si[i].x<-LX) si[i].x+=LEN_X;
131 // si[i].y+=(tau2*si[i].fy/m2);
132 // if(si[i].y>LY) si[i].y-=LEN_Y;
133 // else if(si[i].y<-LY) si[i].y+=LEN_Y;
134 // si[i].z+=(tau2*si[i].fz/m2);
135 // if(si[i].z>LZ) si[i].z-=LEN_Z;
136 // else if(si[i].z<-LZ) si[i].z+=LEN_Z;
137 // /* calculation of velocities v(t+h/2) */
138 // si[i].vx+=(tau*si[i].fx/m2);
139 // si[i].vy+=(tau*si[i].fy/m2);
140 // si[i].vz+=(tau*si[i].fz/m2);
141 // /* reset of forces */
146 // for(i=0;i<amount_si;i++) {
147 // /* calculation of forces at new positions r(t+h) */
148 // for(j=0;j<i;j++) {
149 // deltax=si[i].x-si[j].x;
150 // if(deltax>LX) deltax-=LEN_X;
151 // else if(-deltax>LX) deltax+=LEN_X;
152 // deltax2=deltax*deltax;
153 // deltay=si[i].y-si[j].y;
154 // if(deltay>LY) deltay-=LEN_Y;
155 // else if(-deltay>LY) deltay+=LEN_Y;
156 // deltay2=deltay*deltay;
157 // deltaz=si[i].z-si[j].z;
158 // if(deltaz>LZ) deltaz-=LEN_Z;
159 // else if(-deltaz>LZ) deltaz+=LEN_Z;
160 // deltaz2=deltaz*deltaz;
161 // distance=deltax2+deltay2+deltaz2;
162 // if(distance<=R2_CUTOFF) {
163 // tmp=1.0/distance; // 1/r^2
165 // tmp*=tmp; // 1/r^4
166 // lj1*=tmp; // 1/r^6
167 // tmp*=tmp; // 1/r^8
169 // lj1*=tmp; // 1/r^14
173 // si[i].fx-=lj*deltax;
174 // si[i].fy-=lj*deltay;
175 // si[i].fz-=lj*deltaz;
176 // si[j].fx+=lj*deltax;
177 // si[j].fy+=lj*deltay;
178 // si[j].fz+=lj*deltaz;
182 // for(i=0;i<amount_si;i++) {
183 // /* calculation of new velocities v(t+h) */
184 // si[i].vx+=(tau*si[i].fx/m2);
185 // si[i].vy+=(tau*si[i].fy/m2);
186 // si[i].vz+=(tau*si[i].fz/m2);
191 // /* rasmol script & xyz file */
192 // sprintf(xyz,"./saves/si-%.15f.xyz",time);
193 // sprintf(ppm,"./video/si-%.15f.ppm",time);
194 // fd1=open(xyz,O_WRONLY|O_CREAT|O_TRUNC);
196 // perror("rasmol xyz file open");
199 // dprintf(fd2,"load xyz %s\n",xyz);
200 // dprintf(fd2,"spacefill 200\n");
201 // dprintf(fd2,"rotate x 11\n");
202 // dprintf(fd2,"rotate y 13\n");
203 // dprintf(fd2,"set ambient 20\n");
204 // dprintf(fd2,"set specular on\n");
205 // dprintf(fd2,"zoom 400\n");
206 // dprintf(fd2,"write ppm %s\n",ppm);
207 // dprintf(fd2,"zap\n");
208 // dprintf(fd1,"%d\nsilicon\n",amount_si+9);
209 // for(i=0;i<amount_si;i++)
210 // dprintf(fd1,"Si %f %f %f %f\n",
211 // si[i].x,si[i].y,si[i].z,time);
212 // dprintf(fd1,"H 0.0 0.0 0.0 %f\n",time);
213 // dprintf(fd1,"He %f %f %f %f\n",LX,LY,LZ,time);
214 // dprintf(fd1,"He %f %f %f %f\n",-LX,LY,LZ,time);
215 // dprintf(fd1,"He %f %f %f %f\n",LX,-LY,LZ,time);
216 // dprintf(fd1,"He %f %f %f %f\n",LX,LY,-LZ,time);
217 // dprintf(fd1,"He %f %f %f %f\n",-LX,-LY,LZ,time);
218 // dprintf(fd1,"He %f %f %f %f\n",-LX,LY,-LZ,time);
219 // dprintf(fd1,"He %f %f %f %f\n",LX,-LY,-LZ,time);
220 // dprintf(fd1,"He %f %f %f %f\n",-LX,-LY,-LZ,time);
225 // /* increase time */
232 // printf(" done\n");