Section RI_G0W0

• Parameters influencing the RI-G0W0 method

• Section path: CP2K_INPUT / ATOM / METHOD / XC / WF_CORRELATION / RI_RPA / RI_G0W0

• This section cannot be repeated.

• This section cites the following reference: [DelBen2013]

• Subsections

  • none

• Keywords

  • CHECK_FIT
  • CONTOUR_DEF_END
  • CONTOUR_DEF_OFFSET
  • CONTOUR_DEF_START
  • CORR_MOS_OCC
  • CORR_MOS_VIRT
  • CROSSING_SEARCH
  • CUTOFF_RADIUS
  • EV_SC_ITER
  • FERMI_LEVEL_OFFSET
  • HF_LIKE_EV_START
  • MAX_ITER_FIT
  • NUMB_POLES
  • OMEGA_MAX_FIT
  • PRINT_FIT_ERROR
  • PRINT_GW_DETAILS
  • SCALING
  • STOP_CRIT
  • TRUNCATION

• Keyword descriptions

  CHECK_FIT
  	CHECK_FIT {Logical}
  	If true, the self-energy on the imaginary axis and the fit are printedthe file self_energy_of_MO__for_imaginary_frequency.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  CONTOUR_DEF_END
  	CONTOUR_DEF_END {Integer}
  	Number of the highest MO for which contour deformation (CD) is enabled and analytic continuation is disabled. If negative, CD is disabled.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: -1
  	Alias names for this keyword: CD_END

  CONTOUR_DEF_OFFSET
  	CONTOUR_DEF_OFFSET {Real}
  	Offset for computing the Z-factor in the contour deformation technique.
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 2.00000000E-002
  	Alias names for this keyword: CD_OFFSET

  CONTOUR_DEF_START
  	CONTOUR_DEF_START {Integer}
  	Number of the lowest MO for which contour deformation (CD) is enabled and analytic continuation is disabled. If negative, CD is disabled.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: -1
  	Alias names for this keyword: CD_START

  CORR_MOS_OCC
  	CORR_MOS_OCC {Integer}
  	Number of occupied MOs whose energies are corrected by RI-G0W0. Counting beginning from HOMO, e.g. 3 corrected occ. MOs correspond to correction of HOMO, HOMO-1 and HOMO-2. Numerical effort and storage of RI-G0W0 increase linearly with this number. In case you want to correct all occ. MOs, insert a number larger than the number of occ. MOs.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 10
  	Alias names for this keyword: CORR_OCC

  CORR_MOS_VIRT
  	CORR_MOS_VIRT {Integer}
  	Number of virtual MOs whose energies are corrected by RI-G0W0. Counting beginning from LUMO, e.g. 3 corrected occ. MOs correspond to correction of LUMO, LUMO+1 and LUMO+2. Numerical effort and storage of RI-G0W0 increase linearly with this number. In case you want to correct all virt. MOs, insert a number larger than the number of virt. MOs.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 10
  	Alias names for this keyword: CORR_VIRT

  CROSSING_SEARCH
  	CROSSING_SEARCH {Keyword}
  	Determines, how the self_energy is evaluated on the real axis.
  	This keyword cannot be repeated and it expects precisely one keyword.
  	Default value: Z_SHOT
  	List of valid keywords: NONE Evaluate the correlation self-energy at the energy eigenvalue of SCF. Z_SHOT Calculate the derivative of Sigma and out of it Z. Then extrapolate using Z

  CUTOFF_RADIUS
  	CUTOFF_RADIUS {Real}
  	Cutoff radius for the truncated Coulomb potential in GW in Angstrom. The cell length seems to be a good choice for the truncation.
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 5.29177209E+000
  	Default unit: [angstrom]

  EV_SC_ITER
  	EV_SC_ITER {Integer}
  	Number of iterations for eigenvalue self-consistency cycle. The computational effort of RPA and GW scales linearly with this number.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 1

  FERMI_LEVEL_OFFSET
  	FERMI_LEVEL_OFFSET {Real}
  	Fermi level for occ. orbitals: e_HOMO + FERMI_LEVEL_OFFSET; Fermi level for virt. orbitals: e_LUMO - FERMI_LEVEL_OFFSET. In case e_homo + FERMI_LEVEL_OFFSET < e_lumo - FERMI_LEVEL_OFFSET,we set Fermi level = (e_HOMO+e_LUMO)/2
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 2.00000000E-002

  HF_LIKE_EV_START
  	HF_LIKE_EV_START {Logical}
  	If true, take as input for GW/RPA corrected HF-like eigenvalues according to PRB 83, 115103 (2011), Sec. IV.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  MAX_ITER_FIT
  	MAX_ITER_FIT {Integer}
  	Maximum number of iterations for the Levenberg-Marquard fit.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 10000

  NUMB_POLES
  	NUMB_POLES {Integer}
  	Number of poles for the fitting. Usually, two poles are sufficient.
  	This keyword cannot be repeated and it expects precisely one integer.
  	Default value: 2

  OMEGA_MAX_FIT
  	OMEGA_MAX_FIT {Real}
  	Determines fitting range for the self-energy on the imaginary axis: [0, OMEGA_MAX_FIT] for virt orbitals, [-OMEGA_MAX_FIT,0] for occ orbitals. Unit: Hartree. Default: 0.734996 H = 20 eV.
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 7.34996000E-001

  PRINT_FIT_ERROR
  	PRINT_FIT_ERROR {Logical}
  	Print the statistical error due to the fitting. This error in most cases is very pessimistic (e.g. can be a factor of 10 too large).
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.
  	Alias names for this keyword: FIT_ERROR

  PRINT_GW_DETAILS
  	PRINT_GW_DETAILS {Logical}
  	If true, prints additional information on the quasiparticle energies.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  SCALING
  	SCALING {Real}
  	Set the scaling factor a for the Clenshaw-Curtis grid by hand. If SCALING < 0, a is calculated as for RI-RPA. Until now, the best choice seems to be 0.2. The grid points of the frequency grid are just multiplied by SCALING: omega_j = omega_j*Scaling.
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 2.00000000E-001
  	Alias names for this keyword: A_SCALING

  STOP_CRIT
  	STOP_CRIT {Real}
  	Convergence criterion for the fit. The fitting iteration terminates, if chi^2(n+1)/chi^2(n)-1 < STOP_CRIT.
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.00000000E-005
  	Alias names for this keyword: STOP_CRIT_1

  TRUNCATION
  	TRUNCATION {Logical}
  	If true, the Coulomb potential is truncated. Recommended for periodicsystems.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.