LS_SCF
References: VandeVondele2012
Specifies the parameters of the linear scaling SCF routines [Edit on GitHub]
Subsections
Keywords
Keyword descriptions
- CHECK_S_INV
Type: logical
Default: F
Lone keyword: T
Usage: CHECK_S_INVDescription: Perform an accuracy check on the inverse/sqrt of the s matrix.
- DYNAMIC_THRESHOLD
Type: logical
Default: F
Lone keyword: T
Usage: DYNAMIC_THRESHOLD .TRUE.Description: Should the threshold for the purification be chosen dynamically
- EPS_DIIS
Type: real
Default: 1.00000000E-001
Usage: EPS_DIIS 1.e-1Description: Threshold on the convergence to start using DIIS
- EPS_FILTER
Type: real
Default: 1.00000000E-006
Usage: EPS_FILTER 1.0E-7Description: Threshold used for filtering matrix operations.
Mentions: ⭐PAO-ML
- EPS_LANCZOS
Type: real
Default: 1.00000000E-003
Usage: EPS_LANCZOS 1.0E-4Description: Threshold used for lanczos estimates.
- EPS_SCF
Type: real
Default: 1.00000000E-007
Usage: EPS_SCF 1.e-6Description: Target accuracy for the SCF convergence in terms of change of the total energy per electron.
Mentions: ⭐PAO-ML
- EXTRAPOLATION_ORDER
Type: integer
Default: 4
Usage: EXTRAPOLATION_ORDER 3Description: Number of previous matrices used for the ASPC extrapolation of the initial guess. 0 implies that an atomic guess is used at each step. low (1-2) will result in a drift of the constant of motion during MD. high (>5) might be somewhat unstable, leading to more SCF iterations.
- FIXED_MU
Type: logical
Default: F
Lone keyword: T
Usage: FIXED_MU .TRUE.Description: Should the calculation be performed at fixed chemical potential, or should it be found fixing the number of electrons
- INI_DIIS
Type: integer
Default: 2
Usage: INI_DIIS 2Description: Iteration cycle to start DIIS Kohn-Sham matrix update
- LS_DIIS
Type: logical
Default: F
Lone keyword: T
Usage: LS_DIISDescription: Perform DIIS within linear scaling SCF
- MATRIX_CLUSTER_TYPE
Type: enum
Default: ATOMIC
Usage: MATRIX_CLUSTER_TYPE MOLECULARDescription: Specify how atomic blocks should be clustered in the used matrices, in order to improve flop rate, and possibly speedup the matrix multiply. Note that the atomic s_preconditioner can not be used. Furthermore, since screening is on matrix blocks, slightly more accurate results can be expected with molecular.
Valid values:
ATOMICUsing atomic blocksMOLECULARUsing molecular blocks.
- MAX_DIIS
Type: integer
Default: 4
Usage: MAX_DIIS 4Description: Size of LS_DIIS buffer
- MAX_ITER_LANCZOS
Type: integer
Default: 128
Usage: MAX_ITER_LANCZOSDescription: Maximum number of lanczos iterations.
- MAX_SCF
Type: integer
Default: 20
Usage: MAX_SCF 200Description: Maximum number of SCF iteration to be performed for one optimization
- MIXING_FRACTION
Type: real
Default: 4.50000000E-001
Usage: MIXING_FRACTION 0.4Description: Mixing density matrices uses the specified fraction in the SCF procedure.
- MU
Type: real
Default: -1.00000000E-001
Usage: MU 0.0Description: Value (or initial guess) for the chemical potential, i.e. some suitable energy between HOMO and LUMO energy.
- NMIXING
Type: integer
Default: 2
Usage: NMIXING 2Description: Minimal number of density mixing before start DIIS
- NON_MONOTONIC
Type: logical
Default: T
Lone keyword: T
Usage: NON_MONOTONIC .TRUE.Description: Should the purification be performed non-monotonically. Relevant for TC2 only.
- PERFORM_MU_SCAN
Type: logical
Default: F
Lone keyword: T
Usage: PERFORM_MU_SCANDescription: Do a scan of the chemical potential after the SCF
- PURIFICATION_METHOD
Type: enum
Default: SIGN
Usage: PURIFICATION_METHOD TRS4Description: Scheme used to purify the Kohn-Sham matrix into the density matrix.
Valid values:
SIGNSign matrix iteration.TRS4Trace resetting 4th order schemeTC2Trace conserving 2nd order schemePEXSIPEXSI method
References: VandeVondele2012, Niklasson2003
- REPORT_ALL_SPARSITIES
Type: logical
Default: T
Lone keyword: T
Usage: REPORT_ALL_SPARSITIESDescription: Run the sparsity report at the end of the SCF
- RESTART_READ
Type: logical
Default: F
Lone keyword: T
Usage: RESTART_READDescription: Read the density matrix before the (first) SCF.
- RESTART_WRITE
Type: logical
Default: F
Lone keyword: T
Usage: RESTART_WRITEDescription: Write the density matrix at the end of the SCF (currently requires EXTRAPOLATION_ORDER>0). Files might be rather large.
Mentions: ⭐PAO-ML
- SIGN_METHOD
Type: enum
Default: NEWTONSCHULZ
Usage: SIGN_METHOD NEWTONSCHULZDescription: Method used for the computation of the sign matrix.
Valid values:
NEWTONSCHULZNewton-Schulz iteration.PROOTp-th order root iterationSUBMATRIXSubmatrix method
References: VandeVondele2012, Niklasson2003
- SIGN_ORDER
Type: integer
Default: 2
Usage: SIGN_ORDER 2Description: Order of the method used for the computation of the sign matrix.
- SIGN_SYMMETRIC
Type: logical
Default: F
Lone keyword: T
Usage: SIGN_SYMMETRIC .TRUE.Description: Use symmetric orthogonalization when generating the input for the sign function.
- SUBMATRIX_SIGN_METHOD
Type: enum
Default: NEWTONSCHULZ
Usage: SUBMATRIX_SIGN_METHOD NEWTONSCHULZDescription: Method used for the computation of the sign matrix of all submatrices.
Valid values:
NEWTONSCHULZNewton-Schulz iteration.DIRECTDirect method calculating all eigenvalues.DIRECT_MUADJDirect method with internal adjustment of muDIRECT_MUADJ_LOWMEMDirect method with internal adjustment of mu, using two passes to save memory
- S_INVERSION
Type: enum
Default: SIGN_SQRT
Usage: S_INVERSION MOLECULARDescription: Method used to compute the inverse of S.
Valid values:
SIGN_SQRTUsing the inverse sqrt as obtained from sign function iterations.HOTELLINGUsing the Hotellign iteration.
- S_PRECONDITIONER
Type: enum
Default: ATOMIC
Usage: S_PRECONDITIONER MOLECULARDescription: Preconditions S with some appropriate form.
Valid values:
NONENo preconditionerATOMICUsing atomic blocksMOLECULARUsing molecular sub-blocks. Recommended if molecules are defined and not too large.
- S_SQRT_METHOD
Type: enum
Default: NEWTONSCHULZ
Usage: S_SQRT_METHOD NEWTONSCHULZDescription: Method for the caclulation of the sqrt of S.
Valid values:
NEWTONSCHULZUsing a Newton-Schulz-like iterationPROOTUsing the p-th root method.
- S_SQRT_ORDER
Type: integer
Default: 3
Aliases: SIGN_SQRT_ORDER
Usage: S_SQRT_ORDER 3Description: Order of the iteration method for the calculation of the sqrt of S.