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module dipole_dipole |
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|
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use simulation |
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use definitions |
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use forceGlobals |
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use atype_typedefs |
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|
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contains |
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|
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subroutine dipole_dipole(atom1, atom2, atype1, atype2, dx, dy, dz, rij, & |
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ul1, ul2, rt, rrf, pot) |
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|
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|
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integer atom1, atom2 |
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double precision dx, dy, dz, rij |
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double precision dfact1, dfact2, dip2, r2, r3, r5, pre |
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double precision dudx, dudy, dudz, dudu1x, dudu1y, dudu1z |
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double precision dudu2x, dudu2y, dudu2z, rdotu1, rdotu2, u1dotu2 |
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double precision taper, dtdr, vterm |
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|
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real (kind = dp), dimension(3) :: ul1 |
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real (kind = dp), dimension(3) :: ul2 |
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type (atype), pointer :: atype1 |
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type (atype), pointer :: atype2 |
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|
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! pre converts from mu in units of debye to kcal/mol |
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pre = 14.38362d0 |
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|
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if (rij.le.rrf) then |
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|
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if (rij.lt.rt) then |
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taper = 1.0d0 |
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dtdr = 0.0d0 |
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else |
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taper = (rrf + 2.0d0*rij - 3.0d0*rt)*(rrf-rij)**2/ ((rrf-rt)**3) |
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dtdr = 6.0d0*(rij*rij - rij*rt - rij*rrf +rrf*rt)/((rrf-rt)**3) |
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endif |
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|
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r2 = rij*rij |
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r3 = r2*rij |
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r5 = r3*r2 |
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|
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rdotu1 = dx*ul1(1) + dy*ul1(2) + dz*ul1(3) |
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rdotu2 = dx*ul2(1) + dy*ul2(2) + dz*ul2(3) |
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u1dotu2 = ul1(1)*ul2(1) + ul1(2)*ul2(2) + ul1(3)*ul2(3) |
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|
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dip2 = pre * atype1%dipole_moment * atype2%dipole_moment |
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|
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dfact1 = 3.0d0*dip2 / r2 |
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dfact2 = 3.0d0*dip2 / r5 |
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|
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vterm = dip2*((u1dotu2/r3) - 3.0d0*(rdotu1*rdotu2/r5)) |
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|
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pot = pot + vterm*taper |
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|
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dudx = (-dfact1 * dx * ((u1dotu2/r3) - & |
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(5.0d0*(rdotu1*rdotu2)/r5)) - & |
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dfact2*(ul1(1)*rdotu2 + ul2(1)*rdotu1))*taper + & |
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vterm*dtdr*dx/rij |
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|
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dudy = (-dfact1 * dy * ((u1dotu2/r3) - & |
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(5.0d0*(rdotu1*rdotu2)/r5)) - & |
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dfact2*(ul1(2)*rdotu2 + ul2(2)*rdotu1))*taper + & |
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vterm*dtdr*dy/rij |
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|
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dudz = (-dfact1 * dz * ((u1dotu2/r3) - & |
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(5.0d0*(rdotu1*rdotu2)/r5)) - & |
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dfact2*(ul1(3)*rdotu2 + ul2(3)*rdotu1))*taper + & |
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vterm*dtdr*dz/rij |
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|
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dudu1x = (dip2*((ul2(1)/r3) - (3.0d0*dx*rdotu2/r5)))*taper |
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dudu1y = (dip2*((ul2(2)/r3) - (3.0d0*dy*rdotu2/r5)))*taper |
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dudu1z = (dip2*((ul2(3)/r3) - (3.0d0*dz*rdotu2/r5)))*taper |
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|
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dudu2x = (dip2*((ul1(1)/r3) - (3.0d0*dx*rdotu1/r5)))*taper |
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dudu2y = (dip2*((ul1(2)/r3) - (3.0d0*dy*rdotu1/r5)))*taper |
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dudu2z = (dip2*((ul1(3)/r3) - (3.0d0*dz*rdotu1/r5)))*taper |
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|
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|
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#ifdef IS_MPI |
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fRow(1,atom1) = fRow(1,atom1) + dudx |
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fRow(2,atom1) = fRow(2,atom1) + dudy |
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fRow(3,atom1) = fRow(3,atom1) + dudz |
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|
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fCol(1,atom2) = fCol(1,atom2) - dudx |
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fCol(2,atom2) = fCol(2,atom2) - dudy |
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fCol(3,atom2) = fCol(3,atom2) - dudz |
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|
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tRow(1,atom1) = tRow(1,atom1) - ul1(2)*dudu1z + ul1(3)*dudu1y |
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tRow(2,atom1) = tRow(2,atom1) - ul1(3)*dudu1x + ul1(1)*dudu1z |
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tRow(3,atom1) = tRow(3,atom1) - ul1(1)*dudu1y + ul1(2)*dudu1x |
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|
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tCol(1,atom2) = tCol(1,atom2) - ul2(2)*dudu2z + ul2(3)*dudu2y |
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tCol(2,atom2) = tCol(2,atom2) - ul2(3)*dudu2x + ul2(1)*dudu2z |
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tCol(3,atom2) = tCol(3,atom2) - ul2(1)*dudu2y + ul2(2)*dudu2x |
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#else |
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fTemp(1,atom1) = fTemp(1,atom1) + dudx |
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fTemp(2,atom1) = fTemp(2,atom1) + dudy |
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fTemp(3,atom1) = fTemp(3,atom1) + dudz |
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|
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fTemp(1,atom2) = fTemp(1,atom2) - dudx |
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fTemp(2,atom2) = fTemp(2,atom2) - dudy |
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fTemp(3,atom2) = fTemp(3,atom2) - dudz |
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|
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tTemp(1,atom1) = tTemp(1,atom1) - ul1(2)*dudu1z + ul1(3)*dudu1y |
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tTemp(2,atom1) = tTemp(2,atom1) - ul1(3)*dudu1x + ul1(1)*dudu1z |
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tTemp(3,atom1) = tTemp(3,atom1) - ul1(1)*dudu1y + ul1(2)*dudu1x |
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|
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tTemp(1,atom2) = tTemp(1,atom2) - ul2(2)*dudu2z + ul2(3)*dudu2y |
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tTemp(2,atom2) = tTemp(2,atom2) - ul2(3)*dudu2x + ul2(1)*dudu2z |
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tTemp(3,atom2) = tTemp(3,atom2) - ul2(1)*dudu2y + ul2(2)*dudu2x |
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#endif |
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|
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if (do_stress) then |
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tauTemp(1) = tauTemp(1) + dudx * dx |
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tauTemp(2) = tauTemp(2) + dudx * dy |
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tauTemp(3) = tauTemp(3) + dudx * dz |
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tauTemp(4) = tauTemp(4) + dudy * dx |
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tauTemp(5) = tauTemp(5) + dudy * dy |
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tauTemp(6) = tauTemp(6) + dudy * dz |
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tauTemp(7) = tauTemp(7) + dudz * dx |
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tauTemp(8) = tauTemp(8) + dudz * dy |
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tauTemp(9) = tauTemp(9) + dudz * dz |
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virialTemp = virialTemp + ( tauTemp(1) + tauTemp(5) + tauTemp(9) ) |
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endif |
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|
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endif |
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|
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return |
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end subroutine dipole_dipole |
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|
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end module dipole_dipole |
