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05-force.f90
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05-force.f90
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module mo_force
use mo_syst
use mo_config
use mo_list
use mo_network
implicit none
abstract interface
subroutine abstract_force( tcon, tnb )
import :: con_t, list_t
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
end subroutine
logical function abstract_fun_force( tcon, tnb )
import :: con_t, list_t
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
end function
end interface
contains
logical function calc_fun_force_lj( tcon, tnb )
implicit none
! Warning:
! 1) pay attention to the range of list, make sure it is long enough to cover the interacted particles;
! 2) the texture is 50:50, which is different from the KA model!
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: lainv(free), ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
real(8) :: srinv, srinv3, srinv6, srinv12
integer :: iround(free), cory
integer :: i, j, k, jj
! lj
!! V = econs * exx * [ (sxx/r)^12 - (sxx/r)^6 ]
real(8), parameter :: econs = 4.d0 ! or 1.d0/72.d0
real(8) :: exx, sxx ! dummy coeffcient
real(8), parameter :: eaa = 1.d0, saa = 1.d0
real(8), parameter :: ebb = 0.5d0, sbb = 0.88d0
real(8), parameter :: eab = 1.5d0, sab = 0.8d0
!! cut
real(8), parameter :: rcut = 2.5d0
real(8), parameter :: rcutinv = 1.d0/rcut
!! smooth Vnew(r_cut) = 0
!! smooth Fnew(r_cut) = 0
!! Vnew(r) = V(r) - V(r_cut) - V'(r)*(r-r_cut)
!! energy smooth V(r_cut) = Vcut * ess
real(8), parameter :: Vcut = rcutinv**12 - rcutinv**6
!! force smooth // V'(r_cut) = - 1/sxx * [ 12/r_cut^13 - 6/r_cut^6 ] = Dvcut / sxx * ess
real(8), parameter :: DVcut = - (12*rcutinv**13 - 6*rcutinv**7)
associate( &
natom => tcon%natom, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
if ( present(tnb) ) then
associate(list => tnb%list)
do i=1, natom-1
rai = ra(:,i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
if ( i<=natom/2 .and. j<=natom/2 ) then
exx = eaa
sxx = saa
elseif ( i>natom/2 .and. j>natom/2 ) then
exx = ebb
sxx = sbb
else
exx = eab
sxx = sab
end if
raj = ra(:,j)
dra = raj - rai
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
if ( rij2 > (rcut*sxx)**2 ) cycle
rij = sqrt(rij2)
srinv = sxx / rij
srinv3 = srinv * srinv * srinv
srinv6 = srinv3 * srinv3
srinv12 = srinv6 * srinv6
Ea = Ea + exx * ( srinv12 - srinv6 - Vcut - (DVcut/sxx)*(rij-rcut*sxx) )
! wij = fr * r = - V'(r) * r
wij = exx * ( 12*srinv12 - 6*srinv6 + DVcut/sxx*rij )
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end associate
else
lainv = 1.d0 / la
do i=1, natom-1
rai = ra(:,i)
do j=i+1, natom
if ( i<=natom/2 .and. j<=natom/2 ) then
exx = eaa
sxx = saa
elseif ( i>natom/2 .and. j>natom/2 ) then
exx = ebb
sxx = sbb
else
exx = eab
sxx = sab
end if
raj = ra(:,j)
dra = raj - rai
cory = nint( dra(free) * lainv(free) )
dra(1) = dra(1) - strain * la(free) * cory
do k=1, free-1
iround(k) = nint( dra(k) * lainv(k) )
end do
iround(free) = cory
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
if ( rij2 > (rcut*sxx)**2 ) cycle
rij = sqrt(rij2)
srinv = sxx / rij
srinv3 = srinv * srinv * srinv
srinv6 = srinv3 * srinv3
srinv12 = srinv6 * srinv6
Ea = Ea + exx * ( srinv12 - srinv6 - Vcut - (DVcut/sxx)*(rij-rcut*sxx) )
! wij = fr * r = - V'(r) * r
wij = exx * ( 12*srinv12 - 6*srinv6 + DVcut/sxx*rij )
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end if
Ea = econs * Ea
fa = econs * fa
stress = econs * stress / product(la) / free
press = econs * wili / product(la) / free
pressxyz = econs * wilixyz / product(la)
end associate
calc_fun_force_lj = .true.
return
end function
logical function calc_fun_force( tcon, tnb )
implicit none
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
real(8) :: lainv(free)
integer :: iround(free), cory
integer :: i, j, k, jj
associate( &
natom => tcon%natom, &
radius => tcon%r, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
if ( present(tnb) ) then
associate(list => tnb%list)
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
if ( rij2 > dij**2 ) cycle
rij = sqrt( rij2 )
Ea = Ea + ( 1.d0 - rij/dij )**alpha/alpha
wij = (1.d0 - rij/dij)**(alpha-1) * rij / dij
wili = wili + wij
fr = wij / rij2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
wilixyz = wilixyz + fr * dra(:)**2
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end associate
else
lainv = 1.d0 / la
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do j=i+1, natom
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
cory = nint( dra(free) * lainv(free) )
dra(1) = dra(1) - strain * la(free) * cory
do k=1, free-1
iround(k) = nint( dra(k) * lainv(k) )
end do
iround(free) = cory
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
if ( rij2 > dij**2 ) cycle
rij = sqrt( rij2 )
Ea = Ea + ( 1.d0 - rij/dij )**alpha/alpha
wij = (1.d0 - rij/dij)**(alpha-1) * rij / dij
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end if
stress = stress / product(la) / free
press = wili / product(la) / free
pressxyz = wilixyz / product(la)
end associate
calc_fun_force = .true.
return
end function
subroutine calc_force( tcon, tnb )
implicit none
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
real(8) :: lainv(free)
integer :: iround(free), cory
integer :: i, j, k, jj
associate( &
natom => tcon%natom, &
radius => tcon%r, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
if ( present(tnb) ) then
associate(list => tnb%list)
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
if ( rij2 > dij**2 ) cycle
rij = sqrt( rij2 )
Ea = Ea + ( 1.d0 - rij/dij )**alpha/alpha
wij = (1.d0 - rij/dij)**(alpha-1) * rij / dij
wili = wili + wij
fr = wij / rij2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
wilixyz = wilixyz + fr * dra(:)**2
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end associate
else
lainv = 1.d0 / la
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do j=i+1, natom
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
cory = nint( dra(free) * lainv(free) )
dra(1) = dra(1) - strain * la(free) * cory
do k=1, free-1
iround(k) = nint( dra(k) * lainv(k) )
end do
iround(free) = cory
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
if ( rij2 > dij**2 ) cycle
rij = sqrt( rij2 )
Ea = Ea + ( 1.d0 - rij/dij )**alpha/alpha
wij = (1.d0 - rij/dij)**(alpha-1) * rij / dij
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end if
stress = stress / product(la) / free
press = wili / product(la) / free
pressxyz = wilixyz / product(la)
end associate
end subroutine
subroutine calc_force_gel( tcon, tnb )
implicit none
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
! gel
real(8), parameter :: rcut = 0.1d0
real(8), parameter :: kout = 0.5d0
real(8) :: rc
real(8), dimension(free) :: rai, raj, dra
real(8) :: ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
real(8) :: dijrcut, dijrc
integer :: iround(free), cory
integer :: i, j, k, jj
rc = rcut * kout / ( 1.d0 + kout )
associate( &
natom => tcon%natom, &
radius => tcon%r, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz, &
list => tnb%list &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
dijrcut = dij * ( 1.d0 + rcut )
dijrc = dij * ( 1.d0 + rc )
if ( rij2 > dijrcut**2 ) cycle
rij = sqrt( rij2 )
if ( rij < dij ) then
Ea = Ea + ( 1.d0 - rij/dij )**2/2.d0
wij = (1.d0 - rij/dij) * rij / dij
elseif ( rij < dijrc ) then
Ea = Ea + kout*( 1.d0 - rij/dij )**2/2.d0
wij = kout*(1.d0 - rij/dij) * rij / dij
elseif ( rij < dijrcut ) then
wij = - kout * ( (dijrcut - rij)/dij ) * rij / dij
end if
wili = wili + wij
fr = wij / rij2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
wilixyz = wilixyz + fr * dra(:)**2
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
stress = stress / product(la) / free
press = wili / product(la) / free
pressxyz = wilixyz / product(la)
end associate
end subroutine
subroutine calc_force_pin( tcon, tnb )
implicit none
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
integer :: iround(free), cory
integer :: i, j, k, jj
associate( &
natom => tcon%natom, &
radius => tcon%r, &
ra => tcon%ra, &
fa => tcon%fa, &
pinflag => tcon%pinflag, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz, &
list => tnb%list &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
do i=1, natom
rai = ra(:,i)
ri = radius(i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
raj = ra(:,j)
rj = radius(j)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
dij = ri + rj
if ( rij2 > dij**2 ) cycle
rij = sqrt( rij2 )
Ea = Ea + ( 1.d0 - rij/dij )**alpha/alpha
wij = (1.d0 - rij/dij)**(alpha-1) * rij / dij
wili = wili + wij
fr = wij / rij2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
if ( pinflag(i) == 0 .and. pinflag(j) == 0 ) then
wilixyz = wilixyz + fr * dra(:)**2
stress = stress - 2 * dra(1) * dra(2) * fr
end if
end do
end do
stress = stress / product(la) / free
press = wili / product(la) / free
pressxyz = wilixyz / product(la)
end associate
end subroutine
subroutine calc_force_lj( tcon, tnb )
implicit none
! Warning:
! 1) pay attention to the range of list, make sure it is long enough to cover the interacted particles;
! 2) the texture is 50:50, which is different from the KA model!
! para list
type(con_t), intent(inout) :: tcon
type(list_t), intent(in), optional :: tnb
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: lainv(free), ri, rj, rij2, rij, dij, fr, wij, wili, wilixyz(free)
real(8) :: srinv, srinv3, srinv6, srinv12
integer :: iround(free), cory
integer :: i, j, k, jj
! lj
!! V = econs * exx * [ (sxx/r)^12 - (sxx/r)^6 ]
real(8), parameter :: econs = 4.d0 ! or 1.d0/72.d0
real(8) :: exx, sxx ! dummy coeffcient
real(8), parameter :: eaa = 1.d0, saa = 1.d0
real(8), parameter :: ebb = 0.5d0, sbb = 0.88d0
real(8), parameter :: eab = 1.5d0, sab = 0.8d0
!! cut
real(8), parameter :: rcut = 2.5d0
real(8), parameter :: rcutinv = 1.d0/rcut
!! smooth Vnew(r_cut) = 0
!! smooth Fnew(r_cut) = 0
!! Vnew(r) = V(r) - V(r_cut) - V'(r)*(r-r_cut)
!! energy smooth V(r_cut) = Vcut * ess
real(8), parameter :: Vcut = rcutinv**12 - rcutinv**6
!! force smooth // V'(r_cut) = - 1/sxx * [ 12/r_cut^13 - 6/r_cut^6 ] = Dvcut / sxx * ess
real(8), parameter :: DVcut = - (12*rcutinv**13 - 6*rcutinv**7)
associate( &
natom => tcon%natom, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
if ( present(tnb) ) then
associate(list => tnb%list)
do i=1, natom-1
rai = ra(:,i)
do jj=1, list(i)%nbsum
j = list(i)%nblist(jj)
if ( i<=natom/2 .and. j<=natom/2 ) then
exx = eaa
sxx = saa
elseif ( i>natom/2 .and. j>natom/2 ) then
exx = ebb
sxx = sbb
else
exx = eab
sxx = sab
end if
raj = ra(:,j)
dra = raj - rai
iround = list(i)%iround(:,jj)
cory = list(i)%cory(jj)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
if ( rij2 > (rcut*sxx)**2 ) cycle
rij = sqrt(rij2)
srinv = sxx / rij
srinv3 = srinv * srinv * srinv
srinv6 = srinv3 * srinv3
srinv12 = srinv6 * srinv6
Ea = Ea + exx * ( srinv12 - srinv6 - Vcut - (DVcut/sxx)*(rij-rcut*sxx) )
! wij = fr * r = - V'(r) * r
wij = exx * ( 12*srinv12 - 6*srinv6 + DVcut/sxx*rij )
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end associate
else
lainv = 1.d0 / la
do i=1, natom-1
rai = ra(:,i)
do j=i+1, natom
if ( i<=natom/2 .and. j<=natom/2 ) then
exx = eaa
sxx = saa
elseif ( i>natom/2 .and. j>natom/2 ) then
exx = ebb
sxx = sbb
else
exx = eab
sxx = sab
end if
raj = ra(:,j)
dra = raj - rai
cory = nint( dra(free) * lainv(free) )
dra(1) = dra(1) - strain * la(free) * cory
do k=1, free-1
iround(k) = nint( dra(k) * lainv(k) )
end do
iround(free) = cory
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
if ( rij2 > (rcut*sxx)**2 ) cycle
rij = sqrt(rij2)
srinv = sxx / rij
srinv3 = srinv * srinv * srinv
srinv6 = srinv3 * srinv3
srinv12 = srinv6 * srinv6
Ea = Ea + exx * ( srinv12 - srinv6 - Vcut - (DVcut/sxx)*(rij-rcut*sxx) )
! wij = fr * r = - V'(r) * r
wij = exx * ( 12*srinv12 - 6*srinv6 + DVcut/sxx*rij )
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr
end do
end do
end if
Ea = econs * Ea
fa = econs * fa
stress = econs * stress / product(la) / free
press = econs * wili / product(la) / free
pressxyz = econs * wilixyz / product(la)
end associate
end subroutine
subroutine calc_force_spring( tcon, tnet )
implicit none
! para list
type(con_t), intent(inout) :: tcon
type(network_t), intent(in), optional :: tnet
! local
real(8), dimension(free) :: rai, raj, dra
real(8) :: rij2, rij, l0, fr, wij, wili, wilixyz(free), ks
integer :: iround(free), cory
integer :: i, j, k, ii
associate( &
natom => tcon%natom, &
radius => tcon%r, &
ra => tcon%ra, &
fa => tcon%fa, &
Ea => tcon%Ea, &
la => tcon%la, &
strain => tcon%strain, &
stress => tcon%stress, &
press => tcon%press, &
pressxyz => tcon%pressxyz, &
list => tnet%sps, &
nlist => tnet%nsps &
)
Ea = 0.d0
fa = 0.d0
stress = 0.d0
wili = 0.d0; wilixyz = 0.d0
do ii=1, nlist
i = list(ii)%i
j = list(ii)%j
cory = list(ii)%cory
iround = list(ii)%iround
l0 = list(ii)%l0
ks = list(ii)%ks
rai = ra(:,i)
raj = ra(:,j)
dra = raj - rai
dra(1) = dra(1) - cory * strain * la(free)
do k=1, free
dra(k) = dra(k) - iround(k) * la(k)
end do
rij2 = sum( dra**2 )
rij = sqrt( rij2 )
Ea = Ea + 0.5d0 * ks * ( l0 - rij )**2
wij = ks * ( l0 - rij ) * rij
wili = wili + wij
fr = wij / rij2
wilixyz = wilixyz + fr * dra(:)**2
fa(:,j) = fa(:,j) + fr * dra
fa(:,i) = fa(:,i) - fr * dra
stress = stress - 2 * dra(1) * dra(2) * fr ! 3d ?
end do
stress = stress / product(la) / free
press = wili / product(la) / free
pressxyz = wilixyz / product(la)
end associate
end subroutine
end module