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|
!
! Copyright (C) 2002-2011 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 cell_base
!------------------------------------------------------------------------------!
USE kinds, ONLY : DP
USE constants, ONLY : pi, bohr_radius_angs
USE io_global, ONLY : stdout
!
IMPLICIT NONE
SAVE
!
! ibrav: index of the bravais lattice (see latgen.f90)
INTEGER :: ibrav
! celldm: old-style parameters of the simulation cell (se latgen.f90)
REAL(DP) :: celldm(6) = (/ 0.0_DP,0.0_DP,0.0_DP,0.0_DP,0.0_DP,0.0_DP /)
! traditional crystallographic cell parameters (alpha=cosbc and so on)
REAL(DP) :: a, b, c, cosab, cosac, cosbc
! format of input cell parameters:
! 'alat','bohr','angstrom'
CHARACTER(len=80) :: cell_units
! alat: lattice parameter - often used to scale quantities, or
! in combination to other parameters/constants to define new units
REAL(DP) :: alat = 0.0_DP
! omega: volume of the simulation cell
REAl(DP) :: omega = 0.0_DP
! tpiba: 2 PI/alat, tpiba2=tpiba^2
REAL(DP) :: tpiba = 0.0_DP, tpiba2 = 0.0_DP
! direct and reciprocal lattice primitive vectors
! at(:,i) are the lattice vectors of the simulation cell, a_i,
! in alat units: a_i(:) = at(:,i)/alat
! bg(:,i) are the reciprocal lattice vectors, b_i,
! in tpiba=2pi/alat units: b_i(:) = bg(:,i)/tpiba
REAL(DP) :: at(3,3) = RESHAPE( (/ 0.0_DP /), (/ 3, 3 /), (/ 0.0_DP /) )
REAL(DP) :: bg(3,3) = RESHAPE( (/ 0.0_DP /), (/ 3, 3 /), (/ 0.0_DP /) )
!
! parameters for reference cell
REAL(DP) :: ref_tpiba2 = 0.0_DP
REAL(DP) :: ref_at(3,3) = RESHAPE( (/ 0.0_DP /), (/ 3, 3 /), (/ 0.0_DP /) )
REAL(DP) :: ref_bg(3,3) = RESHAPE( (/ 0.0_DP /), (/ 3, 3 /), (/ 0.0_DP /) )
!
! parameter to store tpiba2 calculated from the input cell parameter
! used in emass_preconditioning, required for restarting variable cell calculation correctly in CP
REAL(DP) :: init_tpiba2 = 0.0_DP
!
! -------------------------------------------------------------------------
! ... periodicity box
! ... In the matrix "a" every row is the vector of each side of
! ... the cell in the real space
TYPE boxdimensions
REAL(DP) :: a(3,3) ! direct lattice generators
REAL(DP) :: m1(3,3) ! reciprocal lattice generators
REAL(DP) :: omega ! cell volume = determinant of a
REAL(DP) :: g(3,3) ! metric tensor
REAL(DP) :: gvel(3,3) ! metric velocity
REAL(DP) :: pail(3,3) ! stress tensor ( scaled coor. )
REAL(DP) :: paiu(3,3) ! stress tensor ( cartesian coor. )
REAL(DP) :: hmat(3,3) ! cell parameters ( transpose of "a" )
REAL(DP) :: hvel(3,3) ! cell velocity
REAL(DP) :: hinv(3,3)
REAL(DP) :: deth
INTEGER :: perd(3)
END TYPE boxdimensions
! The following relations should always be kept valid:
! h = at*alat; ainv = h^(-1); ht=transpose(h)
REAL(DP) :: h(3,3) = 0.0_DP ! simulation cell at time t
REAL(DP) :: ainv(3,3) = 0.0_DP
REAL(DP) :: hold(3,3) = 0.0_DP ! simulation cell at time t-delt
REAL(DP) :: hnew(3,3) = 0.0_DP ! simulation cell at time t+delt
REAL(DP) :: velh(3,3) = 0.0_DP ! simulation cell velocity
REAL(DP) :: deth = 0.0_DP ! determinant of h ( cell volume )
INTEGER :: iforceh(3,3) = 1 ! if iforceh( i, j ) = 0 then h( i, j )
! is not allowed to move
LOGICAL :: enforce_ibrav = .FALSE.! True if ibrav representation is fix
LOGICAL :: fix_volume = .FALSE.! True if cell volume is kept fixed
LOGICAL :: fix_area = .FALSE. ! True if area in xy plane is kept constant
LOGICAL :: isotropic = .FALSE. ! True if volume option is chosen for cell_dofree
REAL(DP) :: wmass = 0.0_DP ! cell fictitious mass
REAL(DP) :: press = 0.0_DP ! external pressure
REAL(DP) :: frich = 0.0_DP ! friction parameter for cell damped dynamics
REAL(DP) :: greash = 1.0_DP ! greas parameter for damped dynamics
LOGICAL :: tcell_base_init = .FALSE.
INTERFACE cell_init
MODULE PROCEDURE cell_init_ht, cell_init_a
END INTERFACE
INTERFACE pbcs
MODULE PROCEDURE pbcs_components, pbcs_vectors
END INTERFACE
INTERFACE s_to_r
MODULE PROCEDURE s_to_r1, s_to_r1b, s_to_r3
END INTERFACE
INTERFACE r_to_s
MODULE PROCEDURE r_to_s1, r_to_s1b, r_to_s3
END INTERFACE
!------------------------------------------------------------------------------!
CONTAINS
!------------------------------------------------------------------------------!
!
SUBROUTINE cell_base_init( ibrav_, celldm_, a_, b_, c_, cosab_, cosac_, &
cosbc_, trd_ht, rd_ht, cell_units_ )
!
! ... initialize cell_base module variables, set up crystal lattice
!
IMPLICIT NONE
INTEGER, INTENT(IN) :: ibrav_
REAL(DP), INTENT(IN) :: celldm_ (6)
LOGICAL, INTENT(IN) :: trd_ht
REAL(DP), INTENT(IN) :: rd_ht (3,3)
CHARACTER(LEN=*), INTENT(IN) :: cell_units_
REAL(DP), INTENT(IN) :: a_ , b_ , c_ , cosab_, cosac_, cosbc_
REAL(DP) :: units
!
IF ( ibrav_ == 0 .and. .not. trd_ht ) THEN
CALL errore('cell_base_init', 'ibrav=0: must read cell parameters', 1)
ELSE IF ( ibrav_ /= 0 .and. trd_ht ) THEN
CALL errore('cell_base_init', 'redundant data for cell parameters', 2)
END IF
!
ibrav = ibrav_
celldm = celldm_
a = a_ ; b = b_ ; c = c_ ; cosab = cosab_ ; cosac = cosac_ ; cosbc = cosbc_
cell_units = cell_units_
units = 0.0_DP
!
IF ( trd_ht ) THEN
!
! ... crystal lattice vectors read from input: find units
!
SELECT CASE ( TRIM( cell_units ) )
CASE ( 'bohr' )
IF( celldm( 1 ) /= 0.0_DP .OR. a /= 0.0_dp ) CALL errore &
('cell_base_init','lattice parameter specified twice',1)
units = 1.0_DP
CASE ( 'angstrom' )
IF( celldm( 1 ) /= 0.0_DP .OR. a /= 0.0_dp ) CALL errore &
('cell_base_init','lattice parameter specified twice',2)
units = 1.0_DP / bohr_radius_angs
CASE ( 'alat' )
IF( celldm( 1 ) /= 0.0_DP ) THEN
units = celldm( 1 )
ELSE IF ( a /= 0.0_dp ) THEN
units = a / bohr_radius_angs
ELSE
CALL errore ('cell_base_init', &
'lattice parameter not specified',1)
END IF
! following case is deprecated and should be removed
CASE ( 'none' )
! cell_units is 'none' if nothing was specified
IF( celldm( 1 ) /= 0.0_DP ) THEN
units = celldm( 1 )
cell_units = 'alat'
ELSE IF ( a /= 0.0_dp ) THEN
units = a / bohr_radius_angs
cell_units = 'alat'
ELSE
units = 1.0_DP
cell_units = 'bohr'
END IF
!
CASE DEFAULT
CALL errore ('cell_base_init', &
'unexpected cell_units '//TRIM(cell_units),1)
END SELECT
!
! ... Beware the transpose operation between matrices ht and at!
!
at = TRANSPOSE( rd_ht ) * units
!
! ... at is in atomic units: find alat, bring at to alat units, find omega
!
IF( celldm( 1 ) /= 0.0_DP ) THEN
alat = celldm( 1 )
ELSE IF ( a /= 0.0_dp ) THEN
alat = a / bohr_radius_angs
ELSE
alat = SQRT ( at(1,1)**2+at(2,1)**2+at(3,1)**2 )
END IF
! for compatibility: celldm still used in phonon etc
celldm(1) = alat
!
at(:,:) = at(:,:) / alat
CALL volume( alat, at(1,1), at(1,2), at(1,3), omega )
!
ELSE
!
! ... crystal lattice vectors via ibrav + celldm parameters
!
IF ( celldm(1) == 0.D0 .and. a /= 0.D0 ) THEN
!
! ... convert crystallographic parameters into celldm parameters
!
CALL abc2celldm ( ibrav, a,b,c,cosab,cosac,cosbc, celldm )
!
ELSE IF ( celldm(1) /= 0.D0 .and. a /= 0.D0 ) THEN
!
CALL errore( 'input', 'do not specify both celldm and a,b,c!', 1 )
!
END IF
!
! ... generate at (in atomic units) from ibrav and celldm
!
CALL latgen( ibrav, celldm, at(1,1), at(1,2), at(1,3), omega )
!
! ... define lattice constants alat, divide at by alat
!
alat = celldm(1)
at(:,:) = at(:,:) / alat
!
END IF
IF ( alat < 1.9_dp ) CALL infomsg ('cell_base_init', &
'DEPRECATED: use true lattice parameter, not A to a.u. conversion factor')
!
! ... Generate the reciprocal lattice vectors
!
CALL recips( at(1,1), at(1,2), at(1,3), bg(1,1), bg(1,2), bg(1,3) )
!
tpiba = 2.0_DP * pi / alat
tpiba2 = tpiba * tpiba
init_tpiba2 = tpiba2 ! BS : this is used in CPV/src/init_run.f90
RETURN
!
END SUBROUTINE cell_base_init
!
SUBROUTINE ref_cell_base_init( ref_alat, rd_ref_ht, ref_cell_units )
!
! ... initialize cell_base module variables, set up crystal lattice
!
IMPLICIT NONE
REAL(DP), INTENT(IN) :: rd_ref_ht (3,3)
REAL(DP), INTENT(INOUT) :: ref_alat
CHARACTER(LEN=*), INTENT(IN) :: ref_cell_units
REAL(DP) :: units, ref_omega
!
! ... reference cell lattice vectors read from REF_CELL_PARAMETERS Card: find units
!
SELECT CASE ( TRIM( ref_cell_units ) )
!
CASE ( 'bohr' )
units = 1.0_DP
CASE ( 'angstrom' )
units = 1.0_DP / bohr_radius_angs
CASE DEFAULT
IF( ref_alat .GT. 0.0_DP ) THEN
units = ref_alat
ELSE
CALL errore('ref_cell_base_init', 'ref_alat must be set to a positive value (in A.U.) in SYSTEM namelist', 1)
END IF
!
END SELECT
!
! ... Beware the transpose operation between matrices ht and at!
!
ref_at = TRANSPOSE( rd_ref_ht ) * units
!
! ... ref_at is in atomic units: find ref_alat, bring ref_at to ref_alat units
!
ref_alat = SQRT ( ref_at(1,1)**2+ref_at(2,1)**2+ref_at(3,1)**2 )
!
ref_at(:,:) = ref_at(:,:) / ref_alat
!
! ... Generate the reciprocal lattice vectors from the reference cell
!
CALL recips( ref_at(1,1), ref_at(1,2), ref_at(1,3), ref_bg(1,1), ref_bg(1,2), ref_bg(1,3) )
!
ref_tpiba2 = (2.0_DP * pi / ref_alat)**2
!
CALL volume( ref_alat, ref_at(1,1), ref_at(1,2), ref_at(1,3), ref_omega )
!
WRITE( stdout, * )
WRITE( stdout, '(3X,"Reference Cell read from REF_CELL_PARAMETERS Card")' )
WRITE( stdout, '(3X,"Reference Cell alat =",F14.8,1X,"A.U.")' ) ref_alat
WRITE( stdout, '(3X,"ref_cell_a1 = ",1X,3f14.8)' ) ref_at(:,1)*ref_alat
WRITE( stdout, '(3X,"ref_cell_a2 = ",1X,3f14.8)' ) ref_at(:,2)*ref_alat
WRITE( stdout, '(3X,"ref_cell_a3 = ",1X,3f14.8)' ) ref_at(:,3)*ref_alat
WRITE( stdout, * )
WRITE( stdout, '(3X,"ref_cell_b1 = ",1X,3f14.8)' ) ref_bg(:,1)/ref_alat
WRITE( stdout, '(3X,"ref_cell_b2 = ",1X,3f14.8)' ) ref_bg(:,2)/ref_alat
WRITE( stdout, '(3X,"ref_cell_b3 = ",1X,3f14.8)' ) ref_bg(:,3)/ref_alat
WRITE( stdout, '(3X,"Reference Cell Volume",F16.8,1X,"A.U.")' ) ref_omega
!
RETURN
!
END SUBROUTINE ref_cell_base_init
!------------------------------------------------------------------------------!
! ... set box
! ... box%m1(i,1) == b1(i) COLUMN are B vectors
! ... box%a(1,i) == a1(i) ROW are A vector
! ... box%omega == volume
! ... box%g(i,j) == metric tensor G
!------------------------------------------------------------------------------!
SUBROUTINE cell_init_ht( what, box, hval )
TYPE (boxdimensions) :: box
REAL(DP), INTENT(IN) :: hval(3,3)
CHARACTER, INTENT(IN) :: what
IF( what == 't' .OR. what == 'T' ) THEN
! hval == ht
box%a = hval
box%hmat = TRANSPOSE( hval )
ELSE
! hval == hmat
box%hmat = hval
box%a = TRANSPOSE( hval )
END IF
CALL gethinv( box )
box%g = MATMUL( box%a(:,:), box%hmat(:,:) )
box%gvel = 0.0_DP
box%hvel = 0.0_DP
box%pail = 0.0_DP
box%paiu = 0.0_DP
RETURN
END SUBROUTINE cell_init_ht
!------------------------------------------------------------------------------!
SUBROUTINE cell_init_a( alat, at, box )
TYPE (boxdimensions) :: box
REAL(DP), INTENT(IN) :: alat, at(3,3)
INTEGER :: i
DO i=1,3
! this is HT: the rows are the lattice vectors
box%a(1,i) = at(i,1)*alat
box%a(2,i) = at(i,2)*alat
box%a(3,i) = at(i,3)*alat
! this is H : the column are the lattice vectors
box%hmat(i,1) = at(i,1)*alat
box%hmat(i,2) = at(i,2)*alat
box%hmat(i,3) = at(i,3)*alat
END DO
box%pail = 0.0_DP
box%paiu = 0.0_DP
box%hvel = 0.0_DP
CALL gethinv(box)
box%g = MATMUL( box%a(:,:), box%hmat(:,:) )
box%gvel = 0.0_DP
RETURN
END SUBROUTINE cell_init_a
!------------------------------------------------------------------------------!
SUBROUTINE r_to_s1 (r,s,box)
REAL(DP), intent(out) :: S(3)
REAL(DP), intent(in) :: R(3)
type (boxdimensions), intent(in) :: box
integer i,j
DO I=1,3
S(I) = 0.0_DP
DO J=1,3
S(I) = S(I) + R(J)*box%m1(J,I)
END DO
END DO
RETURN
END SUBROUTINE r_to_s1
!------------------------------------------------------------------------------!
SUBROUTINE r_to_s3 ( r, s, nat, hinv )
REAL(DP), intent(out) :: S(:,:)
INTEGER, intent(in) :: nat
REAL(DP), intent(in) :: R(:,:)
REAL(DP), intent(in) :: hinv(:,:) ! hinv = TRANSPOSE( box%m1 )
integer :: i, j, ia
DO ia = 1, nat
DO i=1,3
S(i,ia) = 0.0_DP
DO j=1,3
S(i,ia) = S(i,ia) + R(j,ia)*hinv(i,j)
END DO
END DO
END DO
RETURN
END SUBROUTINE r_to_s3
!------------------------------------------------------------------------------!
SUBROUTINE r_to_s1b ( r, s, hinv )
REAL(DP), intent(out) :: S(:)
REAL(DP), intent(in) :: R(:)
REAL(DP), intent(in) :: hinv(:,:) ! hinv = TRANSPOSE( box%m1 )
integer :: i, j
DO I=1,3
S(I) = 0.0_DP
DO J=1,3
S(I) = S(I) + R(J)*hinv(i,j)
END DO
END DO
RETURN
END SUBROUTINE r_to_s1b
!------------------------------------------------------------------------------!
SUBROUTINE s_to_r1 (S,R,box)
REAL(DP), intent(in) :: S(3)
REAL(DP), intent(out) :: R(3)
type (boxdimensions), intent(in) :: box
integer i,j
DO I=1,3
R(I) = 0.0_DP
DO J=1,3
R(I) = R(I) + S(J)*box%a(J,I)
END DO
END DO
RETURN
END SUBROUTINE s_to_r1
!------------------------------------------------------------------------------!
SUBROUTINE s_to_r1b (S,R,h)
REAL(DP), intent(in) :: S(3)
REAL(DP), intent(out) :: R(3)
REAL(DP), intent(in) :: h(:,:) ! h = TRANSPOSE( box%a )
integer i,j
DO I=1,3
R(I) = 0.0_DP
DO J=1,3
R(I) = R(I) + S(J)*h(I,j)
END DO
END DO
RETURN
END SUBROUTINE s_to_r1b
!------------------------------------------------------------------------------!
SUBROUTINE s_to_r3 ( S, R, nat, h )
REAL(DP), intent(in) :: S(:,:)
INTEGER, intent(in) :: nat
REAL(DP), intent(out) :: R(:,:)
REAL(DP), intent(in) :: h(:,:) ! h = TRANSPOSE( box%a )
integer :: i, j, ia
DO ia = 1, nat
DO I = 1, 3
R(I,ia) = 0.0_DP
DO J = 1, 3
R(I,ia) = R(I,ia) + S(J,ia) * h(I,j)
END DO
END DO
END DO
RETURN
END SUBROUTINE s_to_r3
!
!------------------------------------------------------------------------------!
!
SUBROUTINE gethinv(box)
USE matrix_inversion
IMPLICIT NONE
TYPE (boxdimensions), INTENT (INOUT) :: box
!
CALL invmat( 3, box%a, box%m1, box%omega )
box%deth = box%omega
box%hinv = TRANSPOSE( box%m1 )
!
RETURN
END SUBROUTINE gethinv
FUNCTION get_volume( hmat )
IMPLICIT NONE
REAL(DP) :: get_volume
REAL(DP) :: hmat( 3, 3 )
get_volume = hmat(1,1)*(hmat(2,2)*hmat(3,3)-hmat(2,3)*hmat(3,2)) + &
hmat(1,2)*(hmat(2,3)*hmat(3,1)-hmat(2,1)*hmat(3,3)) + &
hmat(1,3)*(hmat(2,1)*hmat(3,2)-hmat(2,2)*hmat(3,1))
RETURN
END FUNCTION get_volume
!
!------------------------------------------------------------------------------!
!
FUNCTION pbc(rin,box,nl) RESULT (rout)
IMPLICIT NONE
TYPE (boxdimensions) :: box
REAL (DP) :: rin(3)
REAL (DP) :: rout(3), s(3)
INTEGER, OPTIONAL :: nl(3)
s = matmul(box%hinv(:,:),rin)
s = s - box%perd*nint(s)
rout = matmul(box%hmat(:,:),s)
IF (present(nl)) THEN
s = REAL( nl, DP )
rout = rout + matmul(box%hmat(:,:),s)
END IF
END FUNCTION pbc
!
!------------------------------------------------------------------------------!
!
SUBROUTINE get_cell_param(box,cell,ang)
IMPLICIT NONE
TYPE(boxdimensions), INTENT(in) :: box
REAL(DP), INTENT(out), DIMENSION(3) :: cell
REAL(DP), INTENT(out), DIMENSION(3), OPTIONAL :: ang
! This code gets the cell parameters given the h-matrix:
! a
cell(1)=sqrt(box%hmat(1,1)*box%hmat(1,1)+box%hmat(2,1)*box%hmat(2,1) &
+box%hmat(3,1)*box%hmat(3,1))
! b
cell(2)=sqrt(box%hmat(1,2)*box%hmat(1,2)+box%hmat(2,2)*box%hmat(2,2) &
+box%hmat(3,2)*box%hmat(3,2))
! c
cell(3)=sqrt(box%hmat(1,3)*box%hmat(1,3)+box%hmat(2,3)*box%hmat(2,3) &
+box%hmat(3,3)*box%hmat(3,3))
IF (PRESENT(ang)) THEN
! gamma
ang(1)=acos((box%hmat(1,1)*box%hmat(1,2)+ &
box%hmat(2,1)*box%hmat(2,2) &
+box%hmat(3,1)*box%hmat(3,2))/(cell(1)*cell(2)))
! beta
ang(2)=acos((box%hmat(1,1)*box%hmat(1,3)+ &
box%hmat(2,1)*box%hmat(2,3) &
+box%hmat(3,1)*box%hmat(3,3))/(cell(1)*cell(3)))
! alpha
ang(3)=acos((box%hmat(1,2)*box%hmat(1,3)+ &
box%hmat(2,2)*box%hmat(2,3) &
+box%hmat(3,2)*box%hmat(3,3))/(cell(2)*cell(3)))
! ang=ang*180.0_DP/pi
ENDIF
END SUBROUTINE get_cell_param
!------------------------------------------------------------------------------!
SUBROUTINE pbcs_components(x1, y1, z1, x2, y2, z2, m)
! ... This subroutine compute the periodic boundary conditions in the scaled
! ... variables system
USE kinds
INTEGER, INTENT(IN) :: M
REAL(DP), INTENT(IN) :: X1,Y1,Z1
REAL(DP), INTENT(OUT) :: X2,Y2,Z2
REAL(DP) MIC
MIC = REAL( M, DP )
X2 = X1 - DNINT(X1/MIC)*MIC
Y2 = Y1 - DNINT(Y1/MIC)*MIC
Z2 = Z1 - DNINT(Z1/MIC)*MIC
RETURN
END SUBROUTINE pbcs_components
!------------------------------------------------------------------------------!
SUBROUTINE pbcs_vectors(v, w, m)
! ... This subroutine compute the periodic boundary conditions in the scaled
! ... variables system
USE kinds
INTEGER, INTENT(IN) :: m
REAL(DP), INTENT(IN) :: v(3)
REAL(DP), INTENT(OUT) :: w(3)
REAL(DP) :: MIC
MIC = REAL( M, DP )
w(1) = v(1) - DNINT(v(1)/MIC)*MIC
w(2) = v(2) - DNINT(v(2)/MIC)*MIC
w(3) = v(3) - DNINT(v(3)/MIC)*MIC
RETURN
END SUBROUTINE pbcs_vectors
!------------------------------------------------------------------------------!
SUBROUTINE set_h_ainv()
!
! CP-PW compatibility: align CP arrays H and ainv to at and bg
!
IMPLICIT NONE
!
!write(stdout,*) 'alat=',alat
!write(stdout,*) 'at=',at
!write(stdout,*) 'bg=',bg
!
h(:,:) = at(:,:)*alat
!
ainv(1,:) = bg(:,1)/alat
ainv(2,:) = bg(:,2)/alat
ainv(3,:) = bg(:,3)/alat
!
END SUBROUTINE set_h_ainv
!------------------------------------------------------------------------------!
SUBROUTINE cell_dyn_init( trd_ht, rd_ht, wc_ , total_ions_mass , press_ , &
frich_ , greash_ , cell_dofree )
USE constants, ONLY: au_gpa, amu_au
USE io_global, ONLY: stdout
IMPLICIT NONE
CHARACTER(LEN=*), INTENT(IN) :: cell_dofree
LOGICAL, INTENT(IN) :: trd_ht
REAL(DP), INTENT(IN) :: rd_ht (3,3)
REAL(DP), INTENT(IN) :: wc_ , frich_ , greash_ , total_ions_mass
REAL(DP), INTENT(IN) :: press_ ! external pressure from input
! ( in KBar = 0.1 GPa )
INTEGER :: j
!
press = press_ / 10.0_DP ! convert press in KBar to GPa
press = press / au_gpa ! convert to AU
! frich = frich_ ! for the time being this is set elsewhere
greash = greash_
WRITE( stdout, 105 )
WRITE( stdout, 110 ) press_
105 format(/,3X,'Simulation Cell Parameters (from input)')
110 format( 3X,'external pressure = ',f15.2,' [KBar]')
wmass = wc_
IF( wmass == 0.0_DP ) THEN
wmass = 3.0_DP / (4.0_DP * pi**2 ) * total_ions_mass
wmass = wmass * AMU_AU
WRITE( stdout,130) wmass
ELSE
WRITE( stdout,120) wmass
END IF
120 format(3X,'wmass (read from input) = ',f15.2,' [AU]')
130 format(3X,'wmass (calculated) = ',f15.2,' [AU]')
IF( wmass <= 0.0_DP ) &
CALL errore(' cell_dyn_init',' wmass out of range ',0)
IF ( trd_ht ) THEN
!
WRITE( stdout, 210 )
WRITE( stdout, 220 ) ( rd_ht( 1, j ), j = 1, 3 )
WRITE( stdout, 220 ) ( rd_ht( 2, j ), j = 1, 3 )
WRITE( stdout, 220 ) ( rd_ht( 3, j ), j = 1, 3 )
!
210 format(3X,'initial cell from CELL_PARAMETERS card')
220 format(3X,3F14.8)
!
END IF
!
ainv(1,:) = bg(:,1)/alat
ainv(2,:) = bg(:,2)/alat
ainv(3,:) = bg(:,3)/alat
!
CALL init_dofree ( cell_dofree )
!
tcell_base_init = .TRUE.
WRITE( stdout, 300 ) ibrav
WRITE( stdout, 305 ) alat
WRITE( stdout, 310 ) at(:,1)*alat
WRITE( stdout, 320 ) at(:,2)*alat
WRITE( stdout, 330 ) at(:,3)*alat
WRITE( stdout, * )
WRITE( stdout, 350 ) bg(:,1)/alat
WRITE( stdout, 360 ) bg(:,2)/alat
WRITE( stdout, 370 ) bg(:,3)/alat
WRITE( stdout, 340 ) omega
300 FORMAT( 3X, 'ibrav = ',I4)
305 FORMAT( 3X, 'alat = ',F14.8)
310 FORMAT( 3X, 'a1 = ',3F14.8)
320 FORMAT( 3X, 'a2 = ',3F14.8)
330 FORMAT( 3X, 'a3 = ',3F14.8)
350 FORMAT( 3X, 'b1 = ',3F14.8)
360 FORMAT( 3X, 'b2 = ',3F14.8)
370 FORMAT( 3X, 'b3 = ',3F14.8)
340 FORMAT( 3X, 'omega = ',F16.8)
RETURN
END SUBROUTINE cell_dyn_init
!------------------------------------------------------------------------------!
SUBROUTINE init_dofree ( cell_dofree )
! set constraints on cell dynamics/optimization
CHARACTER(LEN=*), INTENT(IN) :: cell_dofree
SELECT CASE ( TRIM( cell_dofree ) )
CASE ( 'all', 'default' )
iforceh = 1
CASE ( 'ibrav')
iforceh = 1
enforce_ibrav = .true.
CASE ( 'shape' )
iforceh = 1
fix_volume = .true.
! 2DSHAPE: CASE FOR SHAPE CHANGE IN xy PLANE WITH CONST AREA
! contribution from Richard Charles Andrew
! Physics Department, University of Pretoria
! South Africa, august 2012.
CASE ( '2Dshape' )
iforceh = 1
iforceh(3,3) = 0
iforceh(1,3) = 0
iforceh(3,1) = 0
iforceh(2,3) = 0
iforceh(3,2) = 0
fix_area = .true.
! 2DSHAPE
CASE ( 'volume' )
!CALL errore(' init_dofree ', &
! ' cell_dofree = '//TRIM(cell_dofree)//' not yet implemented ', 1 )
IF ( ibrav /= 1 ) THEN
CALL errore('cell_dofree', 'Isotropic expansion is only allowed for ibrav=1; i.e. for simple cubic', 1)
END IF
iforceh = 0
iforceh(1,1) = 1
iforceh(2,2) = 1
iforceh(3,3) = 1
isotropic = .TRUE.
CASE ('x')
iforceh = 0
iforceh(1,1) = 1
CASE ('y')
iforceh = 0
iforceh(2,2) = 1
CASE ('z')
iforceh = 0
iforceh(3,3) = 1
CASE ('xy')
iforceh = 0
iforceh(1,1) = 1
iforceh(2,2) = 1
! ... if you want the entire xy plane to be free, uncomment:
! iforceh(1,2) = 1
! iforceh(2,1) = 1
! 2DSHAPE THE ENTIRE xy PLANE IS FREE
CASE ('2Dxy')
iforceh = 0
iforceh(1,1) = 1
iforceh(2,2) = 1
iforceh(1,2) = 1
iforceh(2,1) = 1
! 2DSHAPE
CASE ('xz')
iforceh = 0
iforceh(1,1) = 1
iforceh(3,3) = 1
CASE ('yz')
iforceh = 0
iforceh(2,2) = 1
iforceh(3,3) = 1
CASE ('xyz')
iforceh = 0
iforceh(1,1) = 1
iforceh(2,2) = 1
iforceh(3,3) = 1
! epitaxial constraints (2 axes fixed, one free)
! added by ulrich.aschauer@dcb.unibe.ch on 2018-02-02
CASE ('epitaxial_ab')
!fix the a and b axis while allowing c to change
iforceh = 0
iforceh(1,3) = 1
iforceh(2,3) = 1
iforceh(3,3) = 1
CASE ('epitaxial_ac')
!fix the a and c axis while allowing b to change
iforceh = 0
iforceh(1,2) = 1
iforceh(2,2) = 1
iforceh(3,2) = 1
CASE ('epitaxial_bc')
!fix the b and c axis while allowing a to change
iforceh = 0
iforceh(1,1) = 1
iforceh(2,1) = 1
iforceh(3,1) = 1
CASE DEFAULT
CALL errore(' init_dofree ',' unknown cell_dofree '//TRIM(cell_dofree), 1 )
END SELECT
END SUBROUTINE init_dofree
!------------------------------------------------------------------------------!
SUBROUTINE cell_base_reinit( ht )
USE control_flags, ONLY: iverbosity
IMPLICIT NONE
REAL(DP), INTENT(IN) :: ht (3,3)
INTEGER :: j
alat = sqrt( ht(1,1)*ht(1,1) + ht(1,2)*ht(1,2) + ht(1,3)*ht(1,3) )
tpiba = 2.0_DP * pi / alat
tpiba2 = tpiba * tpiba
!
IF( iverbosity > 2 ) THEN
WRITE( stdout, 210 )
WRITE( stdout, 220 ) ( ht( 1, j ), j = 1, 3 )
WRITE( stdout, 220 ) ( ht( 2, j ), j = 1, 3 )
WRITE( stdout, 220 ) ( ht( 3, j ), j = 1, 3 )
END IF
210 format(3X,'Simulation cell parameters with the new cell:')
220 format(3X,3F14.8)
! matrix "ht" used in CP is the transpose of matrix "at"
! times the lattice parameter "alat"; matrix "ainv" is "bg" divided alat
!
at = TRANSPOSE( ht ) / alat
!
CALL recips( at(1,1), at(1,2), at(1,3), bg(1,1), bg(1,2), bg(1,3) )
CALL volume( alat, at(1,1), at(1,2), at(1,3), deth )
omega = deth
!
ainv(1,:) = bg(:,1)/alat
ainv(2,:) = bg(:,2)/alat
ainv(3,:) = bg(:,3)/alat
!
IF( iverbosity > 2 ) THEN
WRITE( stdout, 305 ) alat
WRITE( stdout, 310 ) at(:,1)*alat
WRITE( stdout, 320 ) at(:,2)*alat
WRITE( stdout, 330 ) at(:,3)*alat
WRITE( stdout, * )
WRITE( stdout, 350 ) bg(:,1)/alat
WRITE( stdout, 360 ) bg(:,2)/alat
WRITE( stdout, 370 ) bg(:,3)/alat
WRITE( stdout, 340 ) omega
END IF
305 FORMAT( 3X, 'alat = ',F14.8)
310 FORMAT( 3X, 'a1 = ',3F14.8)
320 FORMAT( 3X, 'a2 = ',3F14.8)
330 FORMAT( 3X, 'a3 = ',3F14.8)
350 FORMAT( 3X, 'b1 = ',3F14.8)
360 FORMAT( 3X, 'b2 = ',3F14.8)
370 FORMAT( 3X, 'b3 = ',3F14.8)
340 FORMAT( 3X, 'omega = ',F14.8)
RETURN
END SUBROUTINE cell_base_reinit
!------------------------------------------------------------------------------!
SUBROUTINE cell_steepest( hnew, h, delt, iforceh, fcell )
REAL(DP), INTENT(OUT) :: hnew(3,3)
REAL(DP), INTENT(IN) :: h(3,3), fcell(3,3)
INTEGER, INTENT(IN) :: iforceh(3,3)
REAL(DP), INTENT(IN) :: delt
INTEGER :: i, j
REAL(DP) :: dt2,fiso
dt2 = delt * delt
!
IF( isotropic ) THEN
!
! Isotropic force on the cell
!
fiso = (fcell(1,1)+fcell(2,2)+fcell(3,3))/3.0_DP
!
DO j=1,3
DO i=1,3
hnew(i,j) = h(i,j) + dt2 * fiso * REAL( iforceh(i,j), DP )
ENDDO
ENDDO
!
ELSE
!
DO j=1,3
DO i=1,3
hnew(i,j) = h(i,j) + dt2 * fcell(i,j) * REAL( iforceh(i,j), DP )
ENDDO
ENDDO
!
END IF
!
RETURN
END SUBROUTINE cell_steepest
!------------------------------------------------------------------------------!
SUBROUTINE cell_verlet( hnew, h, hold, delt, iforceh, fcell, frich, tnoseh, hnos )
REAL(DP), INTENT(OUT) :: hnew(3,3)
REAL(DP), INTENT(IN) :: h(3,3), hold(3,3), hnos(3,3), fcell(3,3)
INTEGER, INTENT(IN) :: iforceh(3,3)
REAL(DP), INTENT(IN) :: frich, delt
LOGICAL, INTENT(IN) :: tnoseh
REAL(DP) :: htmp(3,3)
REAL(DP) :: verl1, verl2, verl3, dt2, ftmp, v1, v2, v3, fiso
INTEGER :: i, j
dt2 = delt * delt
IF( tnoseh ) THEN
ftmp = 0.0_DP
htmp = hnos
ELSE
ftmp = frich
htmp = 0.0_DP
END IF
verl1 = 2.0_DP / ( 1.0_DP + ftmp )
verl2 = 1.0_DP - verl1
verl3 = dt2 / ( 1.0_DP + ftmp )
verl1 = verl1 - 1.0_DP
IF( isotropic ) THEN
!
fiso = (fcell(1,1)+fcell(2,2)+fcell(3,3))/3.0_DP
!
DO j=1,3
DO i=1,3
v1 = verl1 * h(i,j)
v2 = verl2 * hold(i,j)
v3 = verl3 * ( fiso - htmp(i,j) )
hnew(i,j) = h(i,j) + ( v1 + v2 + v3 ) * REAL( iforceh(i,j), DP )
ENDDO
ENDDO
!
ELSE
!
DO j=1,3
DO i=1,3
v1 = verl1 * h(i,j)
v2 = verl2 * hold(i,j)
v3 = verl3 * ( fcell(i,j) - htmp(i,j) )
hnew(i,j) = h(i,j) + ( v1 + v2 + v3 ) * REAL( iforceh(i,j), DP )
ENDDO
ENDDO
!
END IF
RETURN
END SUBROUTINE cell_verlet
!------------------------------------------------------------------------------!
subroutine cell_hmove( h, hold, delt, iforceh, fcell )
REAL(DP), intent(out) :: h(3,3)
REAL(DP), intent(in) :: hold(3,3), fcell(3,3)
REAL(DP), intent(in) :: delt
integer, intent(in) :: iforceh(3,3)
REAL(DP) :: dt2by2, fac
integer :: i, j
dt2by2 = 0.5_DP * delt * delt
fac = dt2by2
do i=1,3
do j=1,3
h(i,j) = hold(i,j) + fac * iforceh(i,j) * fcell(i,j)
end do
end do
return
end subroutine cell_hmove
!------------------------------------------------------------------------------!
subroutine cell_force( fcell, ainv, stress, omega, press, wmassIN )
USE constants, ONLY : eps8
REAL(DP), intent(out) :: fcell(3,3)
REAL(DP), intent(in) :: stress(3,3), ainv(3,3)
REAL(DP), intent(in) :: omega, press
REAL(DP), intent(in), optional :: wmassIN
integer :: i, j
REAL(DP) :: wmass, fiso
IF (.not. present(wmassIN)) THEN
wmass = 1.0
ELSE
wmass = wmassIN
END IF
do j=1,3
do i=1,3
fcell(i,j) = ainv(j,1)*stress(i,1) + ainv(j,2)*stress(i,2) + ainv(j,3)*stress(i,3)
end do
end do
do j=1,3
do i=1,3
fcell(i,j) = fcell(i,j) - ainv(j,i) * press
end do
end do
IF( wmass < eps8 ) &
CALL errore( ' movecell ',' cell mass is less than 0 ! ', 1 )
fcell = omega * fcell / wmass
! added this :
IF( isotropic ) THEN
!
! Isotropic force on the cell
!
fiso = (fcell(1,1)+fcell(2,2)+fcell(3,3))/3.0_DP
do i=1,3
fcell(i,i)=fiso
end do
END IF
!
return
end subroutine cell_force
!------------------------------------------------------------------------------!
subroutine cell_move( hnew, h, hold, delt, iforceh, fcell, frich, tnoseh, vnhh, velh, tsdc )
REAL(DP), intent(out) :: hnew(3,3)
REAL(DP), intent(in) :: h(3,3), hold(3,3), fcell(3,3)
REAL(DP), intent(in) :: vnhh(3,3), velh(3,3)
integer, intent(in) :: iforceh(3,3)
REAL(DP), intent(in) :: frich, delt
logical, intent(in) :: tnoseh, tsdc
REAL(DP) :: hnos(3,3)
hnew = 0.0
if( tnoseh ) then
hnos = vnhh * velh
else
hnos = 0.0_DP
end if
!
IF( tsdc ) THEN
call cell_steepest( hnew, h, delt, iforceh, fcell )
ELSE
call cell_verlet( hnew, h, hold, delt, iforceh, fcell, frich, tnoseh, hnos )
END IF
return
end subroutine cell_move
!------------------------------------------------------------------------------!
SUBROUTINE cell_gamma( hgamma, ainv, h, velh )
!
! Compute hgamma = g^-1 * dg/dt
! that enters in the ions equation of motion
!
IMPLICIT NONE
REAL(DP), INTENT(OUT) :: hgamma(3,3)
REAL(DP), INTENT(IN) :: ainv(3,3), h(3,3), velh(3,3)
REAL(DP) :: gm1(3,3), gdot(3,3)
!
! g^-1 inverse of metric tensor = (ht*h)^-1 = ht^-1 * h^-1
!
gm1 = MATMUL( ainv, TRANSPOSE( ainv ) )
!
! dg/dt = d(ht*h)/dt = dht/dt*h + ht*dh/dt ! derivative of metrix tensor
!
gdot = MATMUL( TRANSPOSE( velh ), h ) + MATMUL( TRANSPOSE( h ), velh )
!
hgamma = MATMUL( gm1, gdot )
!
RETURN
END SUBROUTINE cell_gamma
!------------------------------------------------------------------------------!
SUBROUTINE cell_update_vel( htp, ht0, htm, delt, velh )
!
IMPLICIT NONE
TYPE (boxdimensions) :: htp, ht0, htm
REAL(DP), INTENT(IN) :: delt
REAL(DP), INTENT(OUT) :: velh( 3, 3 )
velh(:,:) = ( htp%hmat(:,:) - htm%hmat(:,:) ) / ( 2.0d0 * delt )
htp%gvel = ( htp%g(:,:) - htm%g(:,:) ) / ( 2.0d0 * delt )
ht0%hvel = velh
RETURN
END SUBROUTINE cell_update_vel
!------------------------------------------------------------------------------!
subroutine cell_kinene( ekinh, temphh, velh )
use constants, only: k_boltzmann_au
implicit none
REAL(DP), intent(out) :: ekinh, temphh(3,3)
REAL(DP), intent(in) :: velh(3,3)
integer :: i,j
ekinh = 0.0_DP
do j=1,3
do i=1,3
ekinh = ekinh + 0.5_DP*wmass*velh(i,j)*velh(i,j)
temphh(i,j) = wmass*velh(i,j)*velh(i,j)/k_boltzmann_au
end do
end do
return
end subroutine cell_kinene
!------------------------------------------------------------------------------!
function cell_alat( )
real(DP) :: cell_alat
if( .NOT. tcell_base_init ) &
call errore( ' cell_alat ', ' alat has not been set ', 1 )
cell_alat = alat
return
end function cell_alat
!
!------------------------------------------------------------------------------!
END MODULE cell_base
!------------------------------------------------------------------------------!
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