sic.c

   1 /*
   2  * sic.c - investigation of the sic precipitation process of silicon carbide
   3  *
   4  * author: Frank Zirkelbach <frank.zirkelbach@physik.uni-augsburg.de>
   5  *
   6  */
   7
   8 #include <math.h>
   9
  10 #include "moldyn.h"
  11 #include "math/math.h"
  12 #include "init/init.h"
  13 #include "visual/visual.h"
  14
  15 #include "posic.h"
  16
  17 int main(int argc,char **argv) {
  18         /* main moldyn structure */
  19         t_moldyn md;
  20
  21         /* potential parameters */
  22         t_lj_params lj;
  23         t_ho_params ho;
  24         t_tersoff_mult_params tp;
  25
  26         /* misc parameters */
  27         double tau;
  28
  29         /* values */
  30         tau=1.0e-15;    /* delta t = 1 fs */
  31
  32         /* initialize moldyn */
  33         printf("[sic] moldyn init\n");
  34         moldyn_init(&md,argc,argv);
  35
  36         /* choose integration algorithm */
  37         printf("[sic] setting integration algorithm\n");
  38         set_int_alg(&md,MOLDYN_INTEGRATE_VERLET);
  39
  40         /* choose potential */
  41         printf("[sic] selecting potential\n");
  42         set_potential1b(&md,tersoff_mult_1bp,&tp);
  43         set_potential2b(&md,tersoff_mult_2bp,&tp);
  44         set_potential3b(&md,tersoff_mult_3bp,&tp);
  45         //set_potential2b(&md,lennard_jones,&lj);
  46
  47         /*
  48          * potential parameters
  49          */
  50
  51         /* lennard jones */
  52         lj.sigma6=LJ_SIGMA_SI*LJ_SIGMA_SI*LJ_SIGMA_SI;
  53         lj.sigma6*=lj.sigma6;
  54         lj.sigma12=lj.sigma6*lj.sigma6;
  55         lj.epsilon4=4.0*LJ_EPSILON_SI;
  56
  57         /* harmonic oscillator */
  58         ho.equilibrium_distance=0.25*sqrt(3.0)*LC_SI;
  59         ho.spring_constant=1;
  60
  61         /*
  62          * tersoff mult potential parameters for SiC
  63          */
  64         tp.S[0]=TM_S_SI;
  65         tp.R[0]=TM_R_SI;
  66         tp.A[0]=TM_A_SI;
  67         tp.B[0]=TM_B_SI;
  68         tp.lambda[0]=TM_LAMBDA_SI;
  69         tp.mu[0]=TM_MU_SI;
  70         tp.beta[0]=TM_BETA_SI;
  71         tp.n[0]=TM_N_SI;
  72         tp.c[0]=TM_C_SI;
  73         tp.d[0]=TM_D_SI;
  74         tp.h[0]=TM_H_SI;
  75
  76         tp.S[1]=TM_S_C;
  77         tp.R[1]=TM_R_C;
  78         tp.A[1]=TM_A_C;
  79         tp.B[1]=TM_B_C;
  80         tp.lambda[1]=TM_LAMBDA_C;
  81         tp.mu[1]=TM_MU_C;
  82         tp.beta[1]=TM_BETA_C;
  83         tp.n[1]=TM_N_C;
  84         tp.c[1]=TM_C_C;
  85         tp.d[1]=TM_D_C;
  86
  87         tp.chi=TM_CHI_SIC;
  88
  89         tersoff_mult_complete_params(&tp);
  90
  91         /* cutoff radius */
  92         printf("[sic] setting cutoff radius\n");
  93         set_cutoff(&md,TM_S_SI);
  94
  95         /* set (initial) dimensions of simulation volume */
  96         printf("[sic] setting dimensions\n");
  97         set_dim(&md,4*LC_SI,4*LC_SI,4*LC_SI,TRUE);
  98
  99         /* set periodic boundary conditions in all directions */
 100         printf("[sic] setting periodic boundary conditions\n");
 101         set_pbc(&md,TRUE,TRUE,TRUE);
 102
 103         /* create the lattice / place atoms */
 104         printf("[sic] creating atoms\n");
 105         create_lattice(&md,DIAMOND,LC_SI,SI,M_SI,
 106                        ATOM_ATTR_1BP|ATOM_ATTR_2BP|ATOM_ATTR_3BP|ATOM_ATTR_HB,
 107                        //ATOM_ATTR_2BP|ATOM_ATTR_HB,
 108                        0,4,4,4);
 109
 110         /* setting a nearest neighbour distance for the moldyn checks */
 111         set_nn_dist(&md,sqrt(3.0)*LC_SI/4.0); /* diamond ! */
 112
 113         /* set temperature */
 114         printf("[sic] setting temperature\n");
 115         set_temperature(&md,0.0);
 116
 117         /* set p/t scaling */
 118         printf("[sic] set p/t scaling\n");
 119         set_pt_scale(&md,0,0,T_SCALE_BERENDSEN,100*tau);
 120
 121         /* initial thermal fluctuations of particles (in equilibrium) */
 122         printf("[sic] thermal init\n");
 123         thermal_init(&md,TRUE);
 124
 125         /* create the simulation schedule */
 126         printf("[sic] adding schedule\n");
 127         moldyn_add_schedule(&md,100,1.0e-15);
 128
 129         /* activate logging */
 130         printf("[sic] activate logging\n");
 131         moldyn_set_log(&md,LOG_TOTAL_ENERGY,"saves/test-energy",1);
 132         moldyn_set_log(&md,VISUAL_STEP,"saves/test-visual",1);
 133
 134         /*
 135          * let's do the actual md algorithm now
 136          *
 137          * integration of newtons equations
 138          */
 139
 140         printf("[sic] integration start, go get a coffee ...\n");
 141         moldyn_integrate(&md);
 142
 143         /* close */
 144
 145         printf("[sic] shutdown\n");
 146         moldyn_shutdown(&md);
 147
 148         return 0;
 149 }
 150