Cleaned RHF

This commit is contained in:
Anthony Scemama 2019-03-01 10:30:02 +01:00
parent 622650a280
commit bdb547c346
3 changed files with 213 additions and 116 deletions

View File

@ -7,6 +7,31 @@ module El = Electrons
module Ao = AOBasis
module Ov = Overlap
type hartree_fock_data =
{
iteration : int ;
coefficients : Mat.t option ;
eigenvalues : Vec.t option ;
error : float option ;
diis : DIIS.t option ;
energy : float option ;
density : Mat.t option ;
fock : Fock.t option ;
}
let empty =
{
iteration = 0 ;
coefficients = None ;
eigenvalues = None ;
error = None ;
diis = None ;
energy = None ;
density = None ;
fock = None ;
}
let make ~guess ~max_scf ~level_shift ~threshold_SCF simulation =
(* Number of occupied MOs *)
let nocc =
@ -16,7 +41,7 @@ let make ~guess ~max_scf ~level_shift ~threshold_SCF simulation =
let nuclear_repulsion =
Si.nuclear_repulsion simulation
in
let ao_basis =
Si.ao_basis simulation
in
@ -45,138 +70,162 @@ let make ~guess ~max_scf ~level_shift ~threshold_SCF simulation =
(* Level shift in MO basis *)
let m_LSmo =
Array.init (Mat.dim2 m_X) (fun i ->
if i > nocc then level_shift else 0.)
if i > nocc then level_shift else 0.)
|> Vec.of_array
|> Mat.of_diag
in
(* SCF iterations *)
let rec loop nSCF iterations energy_prev m_C m_P_prev fock_prev threshold diis =
(* Density matrix over nocc occupied MOs *)
let m_P =
gemm ~alpha:2. ~transb:`T ~k:nocc m_C m_C
(* A single SCF iteration *)
let scf_iteration data =
let nSCF = data.iteration + 1
and m_C = of_some data.coefficients
and m_P_prev = data.density
and fock_prev = data.fock
and diis =
match data.diis with
| Some diis -> diis
| None -> DIIS.make ()
and threshold =
match data.error with
| Some error -> error
| None -> threshold_SCF *. 2.
in
(* Density matrix over nocc occupied MOs *)
let m_P =
gemm ~alpha:2. ~transb:`T ~k:nocc m_C m_C
in
(* Fock matrix in AO basis *)
let fock =
match fock_prev, m_P_prev, threshold > 100. *. threshold_SCF with
| Some fock_prev, Some m_P_prev, true ->
let threshold = 1.e-8 in
Fock.make_rhf ~density:(Mat.sub m_P m_P_prev) ~threshold ao_basis
|> Fock.add fock_prev
| _ -> Fock.make_rhf ~density:m_P ao_basis
in
let m_F, m_Hc, m_J, m_K =
let x = fock in
Fock.(fock x, core x, coulomb x, exchange x)
in
(* Add level shift in AO basis *)
let m_F =
let m_SC =
gemm m_S m_C
in
gemm m_SC (gemm m_LSmo m_SC ~transb:`T)
|> Mat.add m_F
in
(* Fock matrix in AO basis *)
let fock =
match fock_prev, threshold > 100. *. threshold_SCF with
| Some fock_prev, true ->
let threshold = 1.e-8 in
Fock.make_rhf ~density:(Mat.sub m_P m_P_prev) ~threshold ao_basis
|> Fock.add fock_prev
| _ -> Fock.make_rhf ~density:m_P ao_basis
(* Fock matrix in orthogonal basis *)
let m_F_ortho =
xt_o_x m_F m_X
in
let error_fock =
let fps =
gemm m_F (gemm m_P m_S)
and spf =
gemm m_S (gemm m_P m_F)
in
xt_o_x (Mat.sub fps spf) m_X
in
let m_F, m_Hc, m_J, m_K =
let x = fock in
Fock.(fock x, core x, coulomb x, exchange x)
in
(* Add level shift in AO basis *)
let m_F =
let m_SC =
gemm m_S m_C
in
gemm m_SC (gemm m_LSmo m_SC ~transb:`T)
|> Mat.add m_F
let diis =
DIIS.append ~p:(Mat.as_vec m_F_ortho) ~e:(Mat.as_vec error_fock) diis
in
let m_F_diis =
let x =
Bigarray.genarray_of_array1 (DIIS.next diis)
in
Bigarray.reshape_2 x (Mat.dim1 m_F_ortho) (Mat.dim2 m_F_ortho)
in
(* Fock matrix in orthogonal basis *)
let m_F_ortho =
xt_o_x m_F m_X
in
(* MOs in orthogonal MO basis *)
let m_C', eigenvalues =
diagonalize_symm m_F_diis
in
let error_fock =
let fps =
gemm m_F (gemm m_P m_S)
and spf =
gemm m_S (gemm m_P m_F)
in
xt_o_x (Mat.sub fps spf) m_X
in
(* MOs in AO basis *)
let m_C =
gemm m_X m_C'
in
let diis =
DIIS.append ~p:(Mat.as_vec m_F_ortho) ~e:(Mat.as_vec error_fock) diis
in
(* Hartree-Fock energy *)
let energy =
nuclear_repulsion +. 0.5 *.
Mat.gemm_trace m_P (Mat.add m_Hc m_F)
in
let m_F_diis =
let x =
Bigarray.genarray_of_array1 (DIIS.next diis)
in
Bigarray.reshape_2 x (Mat.dim1 m_F_ortho) (Mat.dim2 m_F_ortho)
in
(* Convergence criterion *)
let error =
error_fock
|> Mat.as_vec
|> amax
|> abs_float
in
{
iteration = nSCF ;
eigenvalues = Some eigenvalues ;
coefficients = Some m_C ;
error = Some error ;
diis = Some diis ;
energy = Some energy ;
density = Some m_P ;
fock = Some fock ;
}
(* MOs in orthogonal MO basis *)
let m_C', eigenvalues =
diagonalize_symm m_F_diis
in
(* MOs in AO basis *)
let m_C =
gemm m_X m_C'
in
(* Hartree-Fock energy *)
let energy =
nuclear_repulsion +. 0.5 *.
Mat.gemm_trace m_P (Mat.add m_Hc m_F)
in
(* Convergence criterion *)
let error =
error_fock
|> Mat.as_vec
|> amax
|> abs_float
in
let converged =
nSCF = max_scf || error < threshold_SCF
in
let gap =
if nocc < Vec.dim eigenvalues then
eigenvalues.{nocc+1} -. eigenvalues.{nocc}
else 0.
in
let () =
match energy_prev with
| Some energy_prev ->
Printf.eprintf "%3d %16.10f %16.10f %11.4e %10.4f\n%!" nSCF energy (energy -. energy_prev) error gap
| None ->
Printf.eprintf "%3d %16.10f %16s %11.4e %10.4f\n%!" nSCF energy "" error gap
in
if not converged then
loop (nSCF+1) ( (energy, error, gap) :: iterations) (Some energy) m_C m_P (Some fock) error diis
else
let iterations =
List.rev ( (energy, error, gap) :: iterations )
|> Array.of_list
in
HartreeFock_type.(RHF
{
simulation;
nocc;
guess ;
eigenvectors = m_C ;
eigenvalues ;
energy ;
nuclear_repulsion;
iterations ;
kin_energy = Mat.gemm_trace m_P m_T;
eN_energy = Mat.gemm_trace m_P m_V;
coulomb_energy = 0.5 *. Mat.gemm_trace m_P m_J;
exchange_energy = 0.5 *. Mat.gemm_trace m_P m_K;
occupation = Mat.copy_diag m_P;
})
in
let rec make_iterations_list data =
let energy_prev = data.energy in
(** Perform SCF iteration *)
let data = scf_iteration data in
(** Check convergence *)
let converged, error =
match data.error with
| None -> false, 0.
| Some error -> (data.iteration = max_scf || error < threshold_SCF), error
in
(** Print values *)
let nSCF = data.iteration in
let energy = of_some data.energy in
let () =
match energy_prev with
| Some energy_prev ->
Printf.eprintf "%3d %16.10f %16.10f %11.4e\n%!" nSCF energy (energy -. energy_prev) error
| None ->
Printf.eprintf "%3d %16.10f %16s %11.4e\n%!" nSCF energy "" error
in
if converged then
[ data ]
else
{ empty with
iteration = data.iteration;
energy = data.energy ;
eigenvalues = data.eigenvalues ;
error = data.error ;
} :: (make_iterations_list data)
in
(* Guess coefficients *)
let m_H =
match guess with
@ -193,8 +242,50 @@ let make ~guess ~max_scf ~level_shift ~threshold_SCF simulation =
gemm m_X m_C'
in
let diis = DIIS.make () in
loop 1 [] None m_C m_C None threshold_SCF diis
let iterations_list =
make_iterations_list { empty with coefficients = Some m_C }
in
let iterations, data =
List.map (fun data ->
let gap =
let eigenvalues = of_some data.eigenvalues in
if nocc < Vec.dim eigenvalues then
eigenvalues.{nocc+1} -. eigenvalues.{nocc}
else 0.
and energy = of_some data.energy
and error = of_some data.error
in
(energy, error, gap)
) iterations_list
|> Array.of_list,
List.hd (List.rev iterations_list)
in
let energy = of_some data.energy in
let m_P = of_some data.density in
let fock = of_some data.fock in
let m_J = Fock.coulomb fock in
let m_K = Fock.exchange fock in
HartreeFock_type.(
RHF {
simulation;
nocc;
guess ;
eigenvectors = of_some data.coefficients ;
eigenvalues = of_some data.eigenvalues ;
energy ;
nuclear_repulsion;
iterations ;
kin_energy = Mat.gemm_trace m_P m_T;
eN_energy = Mat.gemm_trace m_P m_V;
coulomb_energy = 0.5 *. Mat.gemm_trace m_P m_J;
exchange_energy = 0.5 *. Mat.gemm_trace m_P m_K;
occupation = Mat.copy_diag m_P;
}
)

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@ -171,6 +171,11 @@ let boys_function ~maxm t =
end
let of_some = function
| Some a -> a
| None -> assert false
(** {2 List functions} *)
let list_some l =

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@ -36,6 +36,7 @@ val chop : float -> (unit -> float) -> float
than {!Constants.epsilon}, and return [a *. f ()].
*)
val of_some : 'a option -> 'a
(** {2 Functions related to the Boys function} *)