/* albe 3 body potential function (first k loop) */
int albe_mult_3bp_k1(t_moldyn *moldyn,
- t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
+ t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
t_albe_mult_params *params;
t_albe_exchange *exchange;
double d_ij,r0;
unsigned char brand;
double S,R,s_r,arg;
+ double energy;
params=moldyn->pot_params;
exchange=&(params->exchange);
}
/* force contribution */
- scale=-0.5*(f_c*(df_r+b*df_a)+df_c*(f_r+b*f_a));
+ scale=-0.5*(f_c*(df_r-b*df_a)+df_c*(f_r-b*f_a));
v3_scale(&force,&(exchange->dist_ij),scale);
v3_add(&(ai->f),&(ai->f),&force);
v3_sub(&(aj->f),&(aj->f),&force); // dri rij = - drj rij
/* virial */
virial_calc(ai,&force,&(exchange->dist_ij));
- /* dzeta prefactor = - 0.5 f_c f_a db */
- exchange->pre_dzeta=-0.5*f_a*f_c*db;
+ /* dzeta prefactor = - f_c f_a db, (* -0.5 due to force calc) */
+ exchange->pre_dzeta=0.5*f_a*f_c*db;
/* energy contribution */
- moldyn->energy+=0.5*f_c*(f_r+b*f_a);
+ energy=0.5*f_c*(f_r-b*f_a);
+ moldyn->energy+=energy;
+ ai->e+=energy;
/* reset k counter for second k loop */
exchange->kcount=0;
/* albe 3 body potential function (second k loop) */
int albe_mult_3bp_k2(t_moldyn *moldyn,
- t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
+ t_atom *ai,t_atom *aj,t_atom *ak,u8 bc) {
t_albe_mult_params *params;
t_albe_exchange *exchange;
/* cos_theta derivatives wrt i,j,k */
dijdik_inv=1.0/(d_ij*d_ik);
- v3_scale(&dcosdrj,&dist_ik,dijdik_inv);
+ v3_scale(&dcosdrj,&dist_ik,dijdik_inv); // j
v3_scale(&tmp,&dist_ij,-cos_theta/d_ij2);
v3_add(&dcosdrj,&dcosdrj,&tmp);
- v3_scale(&dcosdrk,&dist_ij,dijdik_inv);
+ v3_scale(&dcosdrk,&dist_ij,dijdik_inv); // k
v3_scale(&tmp,&dist_ik,-cos_theta/d_ik2);
v3_add(&dcosdrk,&dcosdrk,&tmp);
- v3_add(&dcosdri,&dcosdrj,&dcosdrk);
+ v3_add(&dcosdri,&dcosdrj,&dcosdrk); // i
v3_scale(&dcosdri,&dcosdri,-1.0);
/* f_c_ik * dg, df_c_ik * g */
#endif
/* virial */
- //v3_scale(&force,&force,-1.0);
- //virial_calc(ai,&force,&dist_ij);
+ v3_scale(&force,&force,-1.0);
+ virial_calc(ai,&force,&dist_ij);
/* derivative wrt k */
v3_scale(&force,&dist_ik,-1.0*dfcg); // dri rik = - drk rik
#endif
/* virial */
- //v3_scale(&force,&force,-1.0);
- //virial_calc(ai,&force,&dist_ik);
+ v3_scale(&force,&force,-1.0);
+ virial_calc(ai,&force,&dist_ik);
/* increase k counter */
exchange->kcount++;