quantum-espresso/dft-d3/dftd3_qe.f90

392 lines
14 KiB
Fortran

! Copyright (C) 2017 Quantum ESPRESSO group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
MODULE dftd3_qe
USE dftd3_sizes
USE dftd3_common
USE dftd3_core
USE dftd3_api
IMPLICIT NONE
!
PRIVATE
PUBLIC :: dftd3, dftd3_in, dftd3_xc, dftd3_pbc_gdisp, dftd3_printout, dftd3_clean
PUBLIC :: dftd3_pbc_gdisp_new, dftd3_pbc_hdisp, print_dftd3_hessian
SAVE
!
type(dftd3_calc) :: dftd3
type(dftd3_input):: dftd3_in
CONTAINS
!---------------------------------------------------------------------------
SUBROUTINE print_dftd3_hessian( mat, n, label )
USE kinds, ONLY: DP
USE io_global, ONLY: stdout
IMPLICIT NONE
INTEGER, INTENT(IN) :: n
COMPLEX(DP), INTENT(IN) :: mat(3,n,3,n)
CHARACTER(LEN=*), INTENT(IN) :: label
!
INTEGER :: i, iat, ixyz, j, jat, jxyz
COMPLEX(DP), ALLOCATABLE :: buffer(:)
CHARACTER(LEN=256):: formt, filout, string
!
WRITE(formt,'(A,I9,A)') '(', 2*3*n, 'f24.16)'
WRITE(filout, '(A,A,A)') 'dynamical.',TRIM(label),'.dat'
!
WRITE( stdout, '(/,5x,2A)') 'Writing Hessian on file ', TRIM(filout)
!
ALLOCATE( buffer(3*n) )
!
OPEN (unit = 1, file = TRIM(filout), status = 'unknown')
!
WRITE(1,'(A)') 'Hessian matrix of the Grimme-D3 dispersion term'
WRITE(1,'(A,5I9,3x,L)') 'System: '
!
DO i = 1, 3*n ! 1 2 3 4 5 6 7 8 9 ... 3*nat
iat = (i+2)/3 ! 1 1 1 2 2 2 3 3 3 ... nat
ixyz = i - 3* (iat-1) ! 1 2 3 1 2 3 1 2 3 ... 3
!
DO j = 1, 3*n
jat = (j+2)/3
jxyz = j - 3* (jat-1)
buffer(j) = mat(ixyz,iat,jxyz,jat)
END DO
!
WRITE(1, formt ) buffer(1:3*n)
!
END DO
!
CLOSE (1)
!
DEALLOCATE(buffer)
!
RETURN
!
END SUBROUTINE print_dftd3_hessian
!> Clean memory after a dftd3 calculator is run.
!!
SUBROUTINE dftd3_clean( )
IF (ALLOCATED(dftd3%c6ab)) DEALLOCATE(dftd3%c6ab)
IF (ALLOCATED(dftd3%mxc) ) DEALLOCATE(dftd3%mxc)
IF (ALLOCATED(dftd3%r0ab)) DEALLOCATE(dftd3%r0ab)
END SUBROUTINE dftd3_clean
!> Convert XC labels from QE to those used by DFT-D3
FUNCTION dftd3_xc ( dft )
CHARACTER(LEN=*), INTENT(in) :: dft
CHARACTER(LEN=256) :: dftd3_xc
CHARACTER(LEN=1), EXTERNAL :: lowercase
integer :: i
dftd3_xc = ''
DO i=1,LEN_TRIM(dft)
dftd3_xc(i:i) = lowercase(dft(i:i))
END DO
IF( TRIM(dftd3_xc)=="bp") dftd3_xc="b-p"
IF( TRIM(dftd3_xc)=="blyp") dftd3_xc="b-lyp"
IF( TRIM(dftd3_xc)=="b3lyp") dftd3_xc="b3-lyp"
IF( TRIM(dftd3_xc)=="hse") dftd3_xc="hse06"
IF( TRIM(dftd3_xc)=="pw86pbe") dftd3_xc="rpw86-pbe"
IF( TRIM(dftd3_xc)=="olyp") dftd3_xc="o-lyp"
END FUNCTION dftd3_xc
!> Calculates forces and stress
!! Added interface routine to original Aradi's interface
!! for calculating force and stress separately from the energy.
subroutine dftd3_pbc_gdisp(this, coords, izp, latvecs, &
force_dftd3, stress_dftd3)
type(dftd3_calc), intent(in) :: this
real(wp), intent(in) :: coords(:,:)
integer, intent(in) :: izp(:)
real(wp), intent(in) :: latvecs(:,:)
real(wp), intent(out) :: force_dftd3(:,:), stress_dftd3(:,:)
integer :: natom
real(wp) :: s6, s18, rs6, rs8, rs10, alp6, alp8, alp10
real(wp) :: e6, e8, e10, e12, e6abc, gnorm, disp2
real(wp) :: rtmp3(3)
integer :: rep_cn(3), rep_vdw(3)
natom = size(coords, dim=2)
s6 = this%s6
s18 = this%s18
rs6 = this%rs6
rs8 = this%rs18
rs10 = this%rs18
alp6 = this%alp
alp8 = alp6 + 2.0_wp
alp10 = alp8 + 2.0_wp
call set_criteria(this%rthr, latvecs, rtmp3)
rep_vdw(:) = int(rtmp3) + 1
call set_criteria(this%cn_thr, latvecs, rtmp3)
rep_cn(:) = int(rtmp3) + 1
force_dftd3(:,:) = 0.0_wp
call pbcgdisp(max_elem, maxc, natom, coords, izp, this%c6ab, this%mxc, &
& r2r4, this%r0ab, rcov, s6, s18, rs6, rs8, rs10, alp6, alp8, alp10, &
& this%noabc, this%numgrad, this%version, force_dftd3, disp2, gnorm, &
& stress_dftd3, latvecs, rep_vdw, rep_cn, this%rthr, .false., this%cn_thr)
! Note, the stress variable in pbcgdisp contains the *lattice derivatives*
! on return, so it needs to be converted to obtain the stress tensor.
stress_dftd3(:,:) = -matmul(stress_dftd3, transpose(latvecs))&
& / abs(determinant(latvecs))
end subroutine dftd3_pbc_gdisp
subroutine dftd3_pbc_gdisp_new(this, coords, izp, latvecs, &
force_dftd3, rep_cn_, rep_vdw_)
type(dftd3_calc), intent(in) :: this
real(wp), intent(in) :: coords(:,:)
integer, intent(in) :: izp(:)
real(wp), intent(in) :: latvecs(:,:)
real(wp), intent(out) :: force_dftd3(:,:)
integer, optional, intent(out) :: rep_cn_(3), rep_vdw_(3)
integer :: natom
real(wp) :: s6, s18, rs6, rs8, rs10, alp6, alp8, alp10
real(wp) :: gnorm, disp2
real(wp) :: rtmp3(3)
integer :: rep_cn(3), rep_vdw(3)
real(wp), allocatable :: force_supercell_dftd3(:,:,:,:,:)
natom = size(coords, dim=2)
s6 = this%s6
s18 = this%s18
rs6 = this%rs6
rs8 = this%rs18
rs10 = this%rs18
alp6 = this%alp
alp8 = alp6 + 2.0_wp
alp10 = alp8 + 2.0_wp
call set_criteria(this%rthr, latvecs, rtmp3)
rep_vdw(:) = int(rtmp3) + 1
call set_criteria(this%cn_thr, latvecs, rtmp3)
rep_cn(:) = int(rtmp3) + 1
if(present(rep_cn_)) rep_cn_(:) = rep_cn(:)
if(present(rep_vdw_)) rep_vdw_(:) = rep_vdw(:)
force_dftd3(:,:) = 0.0_wp
allocate( force_supercell_dftd3(-rep_vdw(3):rep_vdw(3),-rep_vdw(2):rep_vdw(2),-rep_vdw(1):rep_vdw(1),3,natom))
call pbcgdisp_new(max_elem, maxc, natom, coords, izp, this%c6ab, this%mxc, &
& r2r4, this%r0ab, rcov, s6, s18, rs6, rs8, rs10, alp6, alp8, alp10, &
& this%noabc, this%numgrad, this%version, force_dftd3, disp2, gnorm, &
& latvecs, rep_vdw, rep_cn, this%rthr, .true., this%cn_thr, &
& 0.0000000010d0, 2, 1, 1, force_supercell_dftd3)
deallocate( force_supercell_dftd3 )
end subroutine dftd3_pbc_gdisp_new
! Calculates the dispersion contribution to Hessian
subroutine dftd3_pbc_hdisp(this, stdout, step, coords, izp, latvecs, rep_cn, rep_vdw, hess_dftd3_, q_gamma )
implicit none
type(dftd3_calc), intent(in) :: this
integer, intent(in) :: stdout
real(wp), intent(in) :: step ! Bohr
real(wp), intent(inout) :: coords(:,:) ! Bohr
! in practice this is a (in). (inout) is only to allow differentiation without further allocations
integer, intent(in) :: izp(:)
real(wp), intent(in) :: latvecs(:,:) ! Bohr
integer, intent(in) :: rep_cn(3), rep_vdw(3)
logical, intent(in) :: q_gamma
real(wp), intent(out), target, contiguous :: hess_dftd3_(:,:,:,:,:,:,:)
real(wp), pointer :: hess_dftd3(:,:,:,:,:,:,:)
integer, allocatable :: ns(:)
real(wp) :: s6, s18, rs6, rs8, rs10, alp6, alp8, alp10
real(wp) :: gnorm, disp2, hnorm
integer :: natom
integer :: iat, ixyz, istep
integer :: irep, jrep, krep
real(wp) :: rtmp3(3), stress_dftd3(3,3)
real(wp), allocatable :: force_dftd3(:,:), force_supercell_dftd3(:,:,:,:,:)
write(stdout, '(/,5x,A)' ) 'Three body terms in DFT-D3 disabled for Hessian calculation'
natom = size(coords, dim=2)
ns = shape(hess_dftd3_)
hess_dftd3( -ns(1)/2:ns(1)/2,-ns(2)/2:ns(2)/2,-ns(3)/2:ns(3)/2, 1:ns(4),1:ns(5),1:ns(6),1:ns(7) ) => hess_dftd3_
if(size(hess_dftd3, dim=5) .ne. natom ) Call errore('dftd3_pbc_hdisp', "Wrong Hessian dimensions", 1)
if(size(hess_dftd3, dim=7) .ne. natom ) Call errore('dftd3_pbc_hdisp', "Wrong Hessian dimensions", 2)
s6 = this%s6
s18 = this%s18
rs6 = this%rs6
rs8 = this%rs18
rs10 = this%rs18
alp6 = this%alp
alp8 = alp6 + 2.0_wp
alp10 = alp8 + 2.0_wp
allocate( force_dftd3(3,natom) )
if(.not.q_gamma) allocate( &
force_supercell_dftd3(-rep_vdw(3):rep_vdw(3),-rep_vdw(2):rep_vdw(2),-rep_vdw(1):rep_vdw(1),3,natom))
hess_dftd3(:,:,:,:,:,:,:) = 0.0_wp
!
! Hessian update:
! h = - 1/2 * ( f+ - f- ) / step
! f+ = -2 * force_from_pbcgdisp(+)
! f- = -2 * force_from_pbcgdisp(-)
! h = ( force_supercell_dftd3(+) - force_supercell_dftd3(-) ) / step
!
do iat = 1, natom
do ixyz = 1, 3
!
if(q_gamma) then ! all periodic images of iat, ixyz will be displaced inside pbcgdisp
!
write(stdout, '(5x,A,2I4,A)' ) 'Displacement step: ', iat, ixyz, ' (+) '
coords(ixyz,iat)=coords(ixyz,iat)+step
force_dftd3(1:3,1:natom) = 0.0_wp
call pbcgdisp(max_elem, maxc, natom, coords, izp, this%c6ab, this%mxc, &
& r2r4, this%r0ab, rcov, s6, s18, rs6, rs8, rs10, alp6, alp8, alp10, &
& .true., .false., this%version, force_dftd3, disp2, gnorm, &
& stress_dftd3, latvecs, rep_vdw, rep_cn, this%rthr, .true., this%cn_thr)
hess_dftd3(0,0,0, ixyz,iat,1:3,1:natom) = hess_dftd3(0,0,0, ixyz,iat,1:3,1:natom) + force_dftd3(1:3,1:natom)
!
write(stdout, '(5x,A,2I4,A)' ) 'Displacement step: ', iat, ixyz, ' (-) '
coords(ixyz,iat)=coords(ixyz,iat)-2*step
force_dftd3(1:3,1:natom) = 0.0_wp
call pbcgdisp(max_elem, maxc, natom, coords, izp, this%c6ab, this%mxc, &
& r2r4, this%r0ab, rcov, s6, s18, rs6, rs8, rs10, alp6, alp8, alp10, &
& .true., .false., this%version, force_dftd3, disp2, gnorm, &
& stress_dftd3, latvecs, rep_vdw, rep_cn, this%rthr, .true., this%cn_thr)
hess_dftd3(0,0,0, ixyz,iat,1:3,1:natom) = hess_dftd3(0,0,0, ixyz,iat,1:3,1:natom) - force_dftd3(1:3,1:natom)
!
coords(ixyz,iat)=coords(ixyz,iat)+step
!
else ! only iat, ixyz in the unit cell will be displaced inside pbcgdisp
!
do istep = -1, 1, 2
write(stdout, '(5x,A,3I4)' ) 'Displacement step: ', iat, ixyz, istep
force_dftd3(:,:) = 0.0_wp ! this is not initialized in pbcgdisp
!force_supercell_dftd3(:,:,:,:,:) = 0.0_wp ! this is initialized in pbcgdisp
call pbcgdisp_new(max_elem, maxc, natom, coords, izp, this%c6ab, this%mxc, &
& r2r4, this%r0ab, rcov, s6, s18, rs6, rs8, rs10, alp6, alp8, alp10, &
& .true., .false., this%version, force_dftd3, disp2, gnorm, &
& latvecs, rep_vdw, rep_cn, this%rthr, .true., this%cn_thr, &
& step, iat, ixyz, istep, force_supercell_dftd3)
do krep = -rep_vdw(3), rep_vdw(3)
do jrep = -rep_vdw(2), rep_vdw(2)
do irep = -rep_vdw(1), rep_vdw(1)
hess_dftd3(krep,jrep,irep, ixyz,iat,1:3,1:natom) = hess_dftd3(krep,jrep,irep, ixyz,iat,1:3,1:natom) &
+ dble(istep) * force_supercell_dftd3(krep,jrep,irep,1:3,1:natom)
end do
end do
end do
!
end do ! istep
!
end if ! q_gamma
!
hnorm=sum(abs(hess_dftd3(0,0,0, ixyz,iat, 1:3,1:natom)))
write(*,*)'|H(unit cell)| =',hnorm
!
end do ! ixyz
end do ! iat
hess_dftd3(:,:,:,:,:,:,:) = hess_dftd3(:,:,:,:,:,:,:) / step
deallocate( force_dftd3 )
if(.not.q_gamma) deallocate( force_supercell_dftd3 )
return
end subroutine dftd3_pbc_hdisp
subroutine dftd3_printout(this, input_dftd3, stdout, nsp, atm, nat, ityp,&
tau, at, alat )
!
! Added subroutine to original interface, which computes things for printout.
! Could also be done in subroutine dftd3_init.
!
type(dftd3_calc), intent(inout) :: this
type(dftd3_input), intent(in) :: input_dftd3
integer, intent(in) :: stdout
integer, intent(in) :: nsp
integer, intent(in) :: nat
character(len=*), intent(in) :: atm(nsp)
integer, intent(in) :: ityp(nat)
real*8, intent(in) :: tau(3,nat)
real*8, intent(in) :: at(3,3)
real*8, intent(in) :: alat
integer :: i,j,ata,z,iz(nat)
real*8 :: cn(nat),rtmp3(3),c6,c8,dum,x
real*8 :: tau_(3,nat)
real*8 :: at_(3,3)
!
!
write(stdout,'( /, 5X, "--------------------------------------------" )' )
if ( input_dftd3%threebody ) then
write(stdout,'( 5X, "DFT-D3 Dispersion Correction (3-body terms):")')
else
write(stdout,'( 5X, "DFT-D3 Dispersion Correction (no 3-body):")')
end if
write(stdout,'( 5X, "--------------------------------------------" , &
& /, 5X, " Reference C6 values for interpolation: ",/, &
& /, 5X, " atom Coordination number C6" )')
!
do i=1,94
do ata=1,nsp
if(i.ne.get_atomic_number(atm(ata))) cycle
do j=1,maxc
if(this%c6ab(i, i, j, j, 1).gt.0) then
write(stdout,'( 9X, A3 , 7X , F6.3, 9X, F8.2)' ) &
atm(ata), this%c6ab(i,i,j,j,2), this%c6ab(i,i,j,j,1)*2.d0
endif
end do
end do
end do
write(stdout,'( /, 7X, "Values used:",/, &
& /, 7X, " atom Coordination number R0_AB[au] C6 C8" )')
!
do ata=1,nat
iz(ata)=get_atomic_number(trim(atm(ityp(ata))))
end do
!
tau_(:,:) = tau(:,:) * alat
at_(:,:) = at(:,:) * alat
CALL set_criteria(this%rthr, at_, rtmp3)
this%rep_vdw(:) = int(rtmp3) + 1
CALL set_criteria(this%cn_thr, at_, rtmp3)
this%rep_cn(:) = int(rtmp3) + 1
CALL pbcncoord(nat, rcov, iz, tau_, cn, at_, this%rep_cn, this%cn_thr)
!
x = 0.d0
do ata = 1, nat
z = get_atomic_number(trim(atm(ityp(ata))))
CALL getc6(maxc,max_elem,this%c6ab,this%mxc, &
& iz(ata),iz(ata),cn(ata),cn(ata),c6)
c8=r2r4(iz(ata))**2*3.0d0*c6
do j = 1, nat
CALL getc6(maxc,max_elem,this%c6ab,this%mxc, &
& iz(ata),iz(j),cn(ata),cn(j),dum)
x = x + dum
enddo
write(stdout,'( 9X, A3 , 7X, F6.3, 10X, F7.3, F10.2, F10.2)') &
atm(ityp(ata)), cn(ata), 0.5*this%r0ab(z,z),c6*2.d0,c8*2.d0
end do
write(stdout,'(/, 9X, "Molecular C6 ( Ry / a.u.^6 ) = ",F12.2,/)') x*2.d0
end subroutine dftd3_printout
END MODULE dftd3_qe