2 * sic.c - investigation of the sic precipitation process of silicon carbide
4 * author: Frank Zirkelbach <frank.zirkelbach@physik.uni-augsburg.de>
14 int hook(void *moldyn,void *hook_params) {
20 /* switch to direct scaling in first hook */
21 if(md->schedule.count==0)
22 set_pt_scale(md,0,0,T_SCALE_BERENDSEN,100.0);
23 /* switch off temp scaling in second hook */
24 if(md->schedule.count==1)
25 set_pt_scale(md,0,0,0,0);
27 //set_temperature(md,md->t_ref-100.0);
32 int main(int argc,char **argv) {
36 printf("[sic] usage: %s <logdir> <temperatur>\n",argv[0]);
40 /* main moldyn structure */
43 /* potential parameters */
46 t_tersoff_mult_params tp;
48 /* testing location & velocity vector */
51 /* initialize moldyn */
52 moldyn_init(&md,argc,argv);
54 /* choose integration algorithm */
55 set_int_alg(&md,MOLDYN_INTEGRATE_VERLET);
57 /* choose potential */
58 //set_potential1b(&md,tersoff_mult_1bp,&tp);
59 //set_potential2b(&md,tersoff_mult_2bp,&tp);
60 //set_potential2b_post(&md,tersoff_mult_post_2bp,&tp);
61 //set_potential3b(&md,tersoff_mult_3bp,&tp);
62 set_potential2b(&md,lennard_jones,&lj);
63 //set_potential2b(&md,harmonic_oscillator,&ho);
66 //set_cutoff(&md,TM_S_SI);
67 set_cutoff(&md,2*LC_SI*0.5*sqrt(1.5));
70 * potential parameters
74 lj.sigma6=LJ_SIGMA_SI*LJ_SIGMA_SI*LJ_SIGMA_SI;
76 lj.sigma12=lj.sigma6*lj.sigma6;
77 lj.epsilon4=4.0*LJ_EPSILON_SI;
78 lj.uc=lj.epsilon4*(lj.sigma12/pow(md.cutoff,12.0)-lj.sigma6/pow(md.cutoff,6));
80 /* harmonic oscillator */
81 ho.equilibrium_distance=0.25*sqrt(3.0)*LC_SI;
82 ho.spring_constant=.1;
85 * tersoff mult potential parameters for SiC
91 tp.lambda[0]=TM_LAMBDA_SI;
93 tp.beta[0]=TM_BETA_SI;
103 tp.lambda[1]=TM_LAMBDA_C;
105 tp.beta[1]=TM_BETA_C;
113 tersoff_mult_complete_params(&tp);
115 /* set (initial) dimensions of simulation volume */
116 set_dim(&md,8*LC_SI*0.5*sqrt(1.5),8*LC_SI*0.5*sqrt(1.5),8*LC_SI*0.5*sqrt(1.5),TRUE);
118 /* set periodic boundary conditions in all directions */
119 set_pbc(&md,TRUE,TRUE,TRUE);
121 /* create the lattice / place atoms */
122 create_lattice(&md,FCC,LC_SI*0.5*sqrt(1.5),SI,M_SI,
123 //create_lattice(&md,DIAMOND,LC_SI,SI,M_SI,
124 // ATOM_ATTR_1BP|ATOM_ATTR_2BP|ATOM_ATTR_3BP|ATOM_ATTR_HB,
125 ATOM_ATTR_2BP|ATOM_ATTR_HB,
127 moldyn_bc_check(&md);
129 /* testing configuration */
130 //r.x=0.28*sqrt(3)*LC_SI/2; v.x=0;
131 //r.x=1.75*LC_SI; v.x=-0.01;
134 //add_atom(&md,SI,M_SI,0,
135 // ATOM_ATTR_1BP|ATOM_ATTR_2BP|ATOM_ATTR_3BP|ATOM_ATTR_HB,
136 // ATOM_ATTR_2BP|ATOM_ATTR_HB,
138 //r.x=-r.x; v.x=-v.x;
141 //add_atom(&md,SI,M_SI,0,
142 // ATOM_ATTR_1BP|ATOM_ATTR_2BP|ATOM_ATTR_3BP|ATOM_ATTR_HB,
143 // ATOM_ATTR_2BP|ATOM_ATTR_HB,
146 /* setting a nearest neighbour distance for the moldyn checks */
147 set_nn_dist(&md,0.25*sqrt(3.0)*LC_SI); /* diamond ! */
149 /* set temperature */
150 //set_temperature(&md,273.0+1410.0);
151 //set_temperature(&md,273.0+450.0);
152 //set_temperature(&md,273.0);
153 //set_temperature(&md,1.0);
154 //set_temperature(&md,0.0);
155 set_temperature(&md,atof(argv[2])+273.0);
158 set_pressure(&md,ATM);
160 /* set p/t scaling */
161 //set_pt_scale(&md,P_SCALE_BERENDSEN,100.0,
162 // T_SCALE_BERENDSEN,100.0);
163 //set_pt_scale(&md,0,0,T_SCALE_DIRECT,1.0);
164 //set_pt_scale(&md,P_SCALE_BERENDSEN,100.0,0,0);
166 /* initial thermal fluctuations of particles (in equilibrium) */
167 thermal_init(&md,TRUE);
169 /* create the simulation schedule */
170 moldyn_add_schedule(&md,1001,1.0);
171 //moldyn_add_schedule(&md,501,1.0);
172 //moldyn_add_schedule(&md,501,1.0);
174 /* schedule hook function */
175 //moldyn_set_schedule_hook(&md,&hook,NULL);
177 /* activate logging */
178 moldyn_set_log_dir(&md,argv[1]);
179 moldyn_set_report(&md,"Frank Zirkelbach","Test 1");
180 moldyn_set_log(&md,LOG_TOTAL_ENERGY,1);
181 moldyn_set_log(&md,VISUAL_STEP,10);
182 moldyn_set_log(&md,CREATE_REPORT,0);
185 * let's do the actual md algorithm now
187 * integration of newtons equations
189 moldyn_integrate(&md);
192 moldyn_shutdown(&md);