| 1070 |
|
|
| 1071 |
|
if (i_is_Quadrupole) then |
| 1072 |
|
if (j_is_Charge) then |
| 1073 |
+ |
! precompute some necessary variables |
| 1074 |
+ |
cx2 = cx_i * cx_i |
| 1075 |
+ |
cy2 = cy_i * cy_i |
| 1076 |
+ |
cz2 = cz_i * cz_i |
| 1077 |
+ |
pref = pre14 * q_j * one_third |
| 1078 |
+ |
|
| 1079 |
|
if (screeningMethod .eq. DAMPED) then |
| 1080 |
|
! assemble the damping variables |
| 1081 |
|
call lookupUniformSpline1d(erfcSpline, rij, erfcVal, derfcVal) |
| 1090 |
|
c4 = 5.0_dp*c3*riji*riji |
| 1091 |
|
endif |
| 1092 |
|
|
| 1093 |
< |
! precompute some variables |
| 1088 |
< |
cx2 = cx_i * cx_i |
| 1089 |
< |
cy2 = cy_i * cy_i |
| 1090 |
< |
cz2 = cz_i * cz_i |
| 1091 |
< |
pref = pre14 * q_j * one_third |
| 1092 |
< |
|
| 1093 |
< |
! calculate the potential |
| 1094 |
< |
pot_term = ( qxx_i * (cx2*c3 - c2ri) + qyy_i * (cy2*c3 - c2ri) + & |
| 1095 |
< |
qzz_i * (cz2*c3 - c2ri) ) |
| 1096 |
< |
|
| 1097 |
< |
vterm = pref * pot_term |
| 1098 |
< |
vpair = vpair + vterm |
| 1099 |
< |
epot = epot + sw*vterm |
| 1100 |
< |
|
| 1101 |
< |
! precompute variables for convenience |
| 1093 |
> |
! precompute some variables for convenience |
| 1094 |
|
preSw = sw*pref |
| 1095 |
|
c2ri = c2*riji |
| 1096 |
|
c3ri = c3*riji |
| 1101 |
|
xhatc4 = xhat*c4rij |
| 1102 |
|
yhatc4 = yhat*c4rij |
| 1103 |
|
zhatc4 = zhat*c4rij |
| 1104 |
+ |
|
| 1105 |
+ |
! calculate the potential |
| 1106 |
+ |
pot_term = ( qxx_i * (cx2*c3 - c2ri) + qyy_i * (cy2*c3 - c2ri) + & |
| 1107 |
+ |
qzz_i * (cz2*c3 - c2ri) ) |
| 1108 |
+ |
|
| 1109 |
+ |
vterm = pref * pot_term |
| 1110 |
+ |
vpair = vpair + vterm |
| 1111 |
+ |
epot = epot + sw*vterm |
| 1112 |
|
|
| 1113 |
|
! calculate the derivatives for the forces and torques |
| 1114 |
|
dudx = dudx - preSw * ( & |
