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module dipole_dipole |
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|
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use force_globals |
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use definitions |
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use atype_module |
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use vector_class |
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use simulation |
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#ifdef IS_MPI |
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use mpiSimulation |
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#endif |
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implicit none |
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|
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real(kind=dp), save :: rrf = 0.0 |
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real(kind=dp), save :: rt = 0.0 |
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real(kind=dp), save :: rrfsq = 0.0 |
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real(kind=dp), save :: pre = 0.0 |
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logical, save :: dipole_initialized = .false. |
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|
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contains |
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|
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subroutine initialize_dipole(this_rrf, this_rt) |
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real(kind=dp), intent(in) :: this_rrf, this_rt |
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rrf = this_rrf |
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rt = this_rt |
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rrfsq = rrf * rrf |
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! pre converts from mu in units of debye to kcal/mol |
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pre = 14.38362_dp |
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|
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dipole_initialized = .true. |
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|
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return |
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end subroutine initialize_dipole |
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|
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|
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subroutine do_dipole_pair(atom1, atom2, d, rij, r2, pot, u_l, f, t, & |
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do_pot, do_stress) |
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|
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logical :: do_pot, do_stress |
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|
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integer atom1, atom2, me1, me2 |
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real(kind=dp) :: rij, mu1, mu2 |
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real(kind=dp) :: dfact1, dfact2, dip2, r2, r3, r5 |
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real(kind=dp) :: dudx, dudy, dudz, dudu1x, dudu1y, dudu1z |
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real(kind=dp) :: dudu2x, dudu2y, dudu2z, rdotu1, rdotu2, u1dotu2 |
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real(kind=dp) :: taper, dtdr, vterm |
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|
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real( kind = dp ) :: pot |
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real( kind = dp ), dimension(3) :: d |
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real( kind = dp ), dimension(3,getNlocal()) :: u_l |
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real( kind = dp ), dimension(3,getNlocal()) :: f |
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real( kind = dp ), dimension(3,getNlocal()) :: t |
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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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|
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if (.not.dipole_initialized) then |
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write(default_error,*) 'Dipole-dipole not initialized!' |
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return |
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endif |
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|
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#ifdef IS_MPI |
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me1 = atid_Row(atom1) |
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ul1(1) = u_l_Row(1,atom1) |
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ul1(2) = u_l_Row(2,atom1) |
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ul1(3) = u_l_Row(3,atom1) |
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|
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me2 = atid_Col(atom2) |
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ul2(1) = u_l_Col(1,atom2) |
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ul2(2) = u_l_Col(2,atom2) |
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ul2(3) = u_l_Col(3,atom2) |
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#else |
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me1 = atid(atom1) |
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ul1(1) = u_l(1,atom1) |
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ul1(2) = u_l(2,atom1) |
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ul1(3) = u_l(3,atom1) |
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|
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me2 = atid(atom2) |
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ul2(1) = u_l(1,atom2) |
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ul2(2) = u_l(2,atom2) |
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ul2(3) = u_l(3,atom2) |
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#endif |
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|
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|
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call getElementProperty(atypes, me1, "dipole_moment", mu1) |
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call getElementProperty(atypes, me2, "dipole_moment", mu2) |
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|
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|
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if (rij.le.rrf) then |
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|
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|
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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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r3 = r2*rij |
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r5 = r3*r2 |
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|
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rdotu1 = d(1)*ul1(1) + d(2)*ul1(2) + d(3)*ul1(3) |
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rdotu2 = d(1)*ul2(1) + d(2)*ul2(2) + d(3)*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 * mu1 * mu2 |
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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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if (do_pot) then |
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#ifdef IS_MPI |
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pot_row(atom1) = pot_row(atom1) + 0.5d0*vterm*taper |
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pot_col(atom2) = pot_col(atom2) + 0.5d0*vterm*taper |
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#else |
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pot = pot + vterm*taper |
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#endif |
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endif |
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|
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dudx = (-dfact1 * d(1) * ((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*d(1)/rij |
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|
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dudy = (-dfact1 * d(2) * ((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*d(2)/rij |
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|
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dudz = (-dfact1 * d(3) * ((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*d(3)/rij |
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|
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dudu1x = (dip2*((ul2(1)/r3) - (3.0d0*d(1)*rdotu2/r5)))*taper |
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dudu1y = (dip2*((ul2(2)/r3) - (3.0d0*d(2)*rdotu2/r5)))*taper |
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dudu1z = (dip2*((ul2(3)/r3) - (3.0d0*d(3)*rdotu2/r5)))*taper |
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|
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dudu2x = (dip2*((ul1(1)/r3) - (3.0d0*d(1)*rdotu1/r5)))*taper |
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dudu2y = (dip2*((ul1(2)/r3) - (3.0d0*d(2)*rdotu1/r5)))*taper |
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dudu2z = (dip2*((ul1(3)/r3) - (3.0d0*d(3)*rdotu1/r5)))*taper |
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|
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|
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#ifdef IS_MPI |
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f_Row(1,atom1) = f_Row(1,atom1) + dudx |
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f_Row(2,atom1) = f_Row(2,atom1) + dudy |
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f_Row(3,atom1) = f_Row(3,atom1) + dudz |
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|
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f_Col(1,atom2) = f_Col(1,atom2) - dudx |
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f_Col(2,atom2) = f_Col(2,atom2) - dudy |
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f_Col(3,atom2) = f_Col(3,atom2) - dudz |
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|
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t_Row(1,atom1) = t_Row(1,atom1) - ul1(2)*dudu1z + ul1(3)*dudu1y |
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t_Row(2,atom1) = t_Row(2,atom1) - ul1(3)*dudu1x + ul1(1)*dudu1z |
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t_Row(3,atom1) = t_Row(3,atom1) - ul1(1)*dudu1y + ul1(2)*dudu1x |
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|
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t_Col(1,atom2) = t_Col(1,atom2) - ul2(2)*dudu2z + ul2(3)*dudu2y |
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t_Col(2,atom2) = t_Col(2,atom2) - ul2(3)*dudu2x + ul2(1)*dudu2z |
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t_Col(3,atom2) = t_Col(3,atom2) - ul2(1)*dudu2y + ul2(2)*dudu2x |
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#else |
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f(1,atom1) = f(1,atom1) + dudx |
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f(2,atom1) = f(2,atom1) + dudy |
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f(3,atom1) = f(3,atom1) + dudz |
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|
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f(1,atom2) = f(1,atom2) - dudx |
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f(2,atom2) = f(2,atom2) - dudy |
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f(3,atom2) = f(3,atom2) - dudz |
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|
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t(1,atom1) = t(1,atom1) - ul1(2)*dudu1z + ul1(3)*dudu1y |
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t(2,atom1) = t(2,atom1) - ul1(3)*dudu1x + ul1(1)*dudu1z |
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t(3,atom1) = t(3,atom1) - ul1(1)*dudu1y + ul1(2)*dudu1x |
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|
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t(1,atom2) = t(1,atom2) - ul2(2)*dudu2z + ul2(3)*dudu2y |
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t(2,atom2) = t(2,atom2) - ul2(3)*dudu2x + ul2(1)*dudu2z |
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t(3,atom2) = t(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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|
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if (molMembershipList(atom1) .ne. molMembershipList(atom2)) then |
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|
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! because the d vector is the rj - ri vector, and |
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! because dudx, dudy, dudz are the (positive) force on |
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! atom i (negative on atom j) we need a negative sign here: |
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|
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tau_Temp(1) = tau_Temp(1) - d(1) * dudx |
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tau_Temp(2) = tau_Temp(2) - d(1) * dudy |
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tau_Temp(3) = tau_Temp(3) - d(1) * dudz |
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tau_Temp(4) = tau_Temp(4) - d(2) * dudx |
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tau_Temp(5) = tau_Temp(5) - d(2) * dudy |
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tau_Temp(6) = tau_Temp(6) - d(2) * dudz |
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tau_Temp(7) = tau_Temp(7) - d(3) * dudx |
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tau_Temp(8) = tau_Temp(8) - d(3) * dudy |
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tau_Temp(9) = tau_Temp(9) - d(3) * dudz |
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|
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virial_Temp = virial_Temp + & |
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(tau_Temp(1) + tau_Temp(5) + tau_Temp(9)) |
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|
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endif |
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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 do_dipole_pair |
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|
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end module dipole_dipole |