XC

Name DFTULevel
Section Hamiltonian::XC
Type integer
Default no

This variable selects which DFT+U expression is added to the Hamiltonian.

Options:

• dft_u_none:
  No +U term is not applied.
  
• dft_u_empirical:
  An empiricial Hubbard U is added on the orbitals specified in the block species with hubbard_l and hubbard_u
  
• dft_u_acbn0:
  Octopus determines the effective U term using the ACBN0 functional as defined in PRX 5, 011006 (2015)
  

Name HFSingularity
Section Hamiltonian::XC
Type integer
Default general

(Experimental) This variable selects the method used for the treatment of the singularity of the Coulomb potential in Hatree-Fock and hybrid-functional DFT calculations. This shoulbe be only applied for periodic systems and is only used for FFT kernels of the Poisson solvers.

Options:

• none:
  The singularity is replaced by zero.
  
• general:
  The general treatment of the singularity, as described in Carrier et al, PRB 75 205126 (2007). This is the default option
  
• fcc:
  The treatment of the singulariy as described in Gygi and Baldereschi, PRB 34, 4405 (1986). This is formally valid for cubic systems only.
  
• spherical_bz:
  The divergence in q=0 is treated analytically assuming a spherical Brillouin zone
  

Name HFSingularityNk
Section Hamiltonian::XC
Type integer
Default 60 in 3D, 1200 in 1D

Number of k-point used (total number of k-points) is (2*Nk+1)^3) in the numerical integration of the auxiliary function f(q). See PRB 75, 205126 (2007) for more details. Only for HFSingularity=general. Also used in 1D.

Name HFSingularityNsteps
Section Hamiltonian::XC
Type integer
Default 7 in 3D, 15 in 1D

Number of grid refinement steps in the numerical integration of the auxiliary function f(q). See PRB 75, 205126 (2007) for more details. Only for HFSingularity=general. Also used in 1D.

Name Interaction1D
Section Hamiltonian::XC
Type integer
Default interaction_soft_coulomb

When running in 1D, one has to soften the Coulomb interaction. This softening is not unique, and several possibilities exist in the literature.

Options:

• interaction_exp_screened:
  Exponentially screened Coulomb interaction. See, e.g., M Casula, S Sorella, and G Senatore, Phys. Rev. B 74, 245427 (2006).
  
• interaction_soft_coulomb:
  Soft Coulomb interaction of the form $1/\sqrt{x^2 + \alpha^2}$.
  

Name Interaction1DScreening
Section Hamiltonian::XC
Type float
Default 1.0

Defines the screening parameter $\alpha$ of the softened Coulomb interaction when running in 1D.

Name KLIPhotonCOC
Section Hamiltonian::XC
Type logical
Default .false.

Activate the center of charge translation of the electric dipole operator which should avoid the dependence of the photon KLI on an permanent dipole.

Name libvdwxcDebug
Section Hamiltonian::XC
Type logical

Dump libvdwxc inputs and outputs to files.

Name libvdwxcMode
Section Hamiltonian::XC
Type integer

Whether libvdwxc should run with serial fftw3, fftw3-mpi, or pfft. to specify fftw3-mpi in serial for debugging. pfft is not implemented at the moment.

Options:

• libvdwxc_mode_auto:
  Use serial fftw3 if actually running in serial, else fftw3-mpi.
  
• libvdwxc_mode_serial:
  Run with serial fftw3. Works only when not parallelizing over domains.
  
• libvdwxc_mode_mpi:
  Run with fftw3-mpi. Works only if Octopus is compiled with MPI.
  

Name libvdwxcVDWFactor
Section Hamiltonian::XC
Type float

Prefactor of non-local van der Waals functional. Setting a prefactor other than one is wrong, but useful for debugging.

Name OEPLevel
Section Hamiltonian::XC
Type integer
Default oep_kli

At what level shall Octopus handle the optimized effective potential (OEP) equation.

Options:

• oep_none:
  Do not solve OEP equation.
  
• oep_kli:
  Krieger-Li-Iafrate (KLI) approximation. Ref: JB Krieger, Y Li, GJ Iafrate, Phys. Lett. A 146, 256 (1990).
  
• oep_full:
  (Experimental) Full solution of OEP equation using the Sternheimer approach. The linear solver will be controlled by the variables in section Linear Response::Solver, and the iterations for OEP by Linear Response::SCF in LR calculations and variable OEPMixing. Note that default for LRMaximumIter is set to 10. Ref: S. Kuemmel and J. Perdew, Phys. Rev. Lett. 90, 043004 (2003).
  

Name OEPMixing
Section Hamiltonian::XC
Type float
Default 1.0

The linear mixing factor used to solve the Sternheimer equation in the full OEP procedure.

Name OEPMixingScheme
Section Hamiltonian::XC
Type integer
Default 1.0



Options:

• OEP_MIXING_SCHEME_CONST:
  
• OEP_MIXING_SCHEME_BB:
  
• OEP_MIXING_SCHEME_DENS:
  

Name OEPRemoveElectron
Section Hamiltonian::XC
Type logical
Default .false.

Remove electron-electron interaction in OEP-Photon calculations

Name PhotonModes
Section Hamiltonian::XC
Type block

Each line of the block should specify one photon mode. The syntax is the following:

%PhotonModes omega1 | lambda1| PolX1 | PolY1 | PolZ1 … %

The first column is the mode frequency, in units of energy. The second column is the coupling strength, in units of energy. The remaining columns specify the polarization direction of the mode. If the polarization vector should be normalized to one. If that is not the case the code will normalize it.

Name PhotonXCEnergyMethod
Section Hamiltonian::XC
Type integer
Default 1

There are different ways to calculate the energy,

Options:

• virial:
  (modified) virial approach
  $ (E_{\rm{px}}^{\rm{virial}} = \frac{1}{2}\int d\mathbf{r}\ \mathbf{r}\cdot[ -\rho(\mathbf{r})\nabla v_{\rm{px}}(\mathbf{r})]) $
  
  
• expectation_value:
  expectation value w.tr.t. the wave functions (valid only for 1 electron)
  $ E_{\rm{px}}[\rho] = -\sum_{\alpha=1}^{M_{p}}\frac{\tilde{\lambda}_{\alpha}^{2}}{2\tilde{\omega}_{\alpha}^{2}} \langle (\tilde{\mathbf{{\varepsilon}}}_{\alpha}\cdot\hat{\mathbf{J}}_{\rm{p}})\Phi[\rho] | (\tilde{\mathbf{{\varepsilon}}}_{\alpha}\cdot\hat{\mathbf{J}}_{\rm{p}})\Phi[\rho] \rangle $
  This option only works for the wave function based electron-photon functionals
  
• LDA:
  energy from electron density
  $ E_{\rm pxLDA}[\rho] = \frac{-2\pi^{2}}{(d+2)({2V_{d}})^{\frac{2}{d}}} \sum_{\alpha=1}^{M_{p}}\frac{\tilde{\lambda}_{\alpha}^{2}}{\tilde{\omega}_{\alpha}^{2}} \int d\mathbf{r}\ \rho^{\frac{2+d}{d}}(\mathbf{r}) $
  This option only works with LDA electron-photon functionals.
  

Name PhotonXCEtaC
Section Hamiltonian::XC
Type float
Default 1.0

The scaling factor for the px potential to reduce the weak coupling perturbation regime

Name PhotonXCLambShift
Section Hamiltonian::XC
Type logical
Default .false.

to deal with the photon free exchange potential for continuum mode in free space

Name PhotonXCLambShiftOmegaCutoff
Section Hamiltonian::XC
Type float
Default 0.0

the cutoff frequency (Ha) for Lamb shift

Name PhotonXCLambShiftRenormalizeMass
Section Hamiltonian::XC
Type logical
Default .false.

to deal with the photon free exchange potential for continuum mode in free space

Name PhotonXCLDAKappa
Section Hamiltonian::XC
Type float
Default 1.0

the scaling factor for px-LDA potential

Name SCDMforPZSIC
Section Hamiltonian::XC
Type logical
Default .false.

If set to .true., the code will use the SCDM method to Wannierize the orbitals before computing the orbital-dependent SIC correction

Name SICCorrection
Section Hamiltonian::XC
Type integer
Default sic_none

This variable controls which form of self-interaction correction to use. Note that this correction will be applied to the functional chosen by XCFunctional.

Options:

• sic_none:
  No self-interaction correction.
  
• sic_pz:
  Perdew-Zunger SIC, handled by the OEP technique. J. P. Perdew and Alex Zunger, Phys. Rev. B 23, 5048 (1981) Extension to the spinor case follows Tancogne-Dejean et al., J. Chem. Phys. 159, 224110 (2023)
  
• sic_amaldi:
  Amaldi correction term. Not implemeneted for spinors. E. Fermi and E. Amaldi, Mem. Reale Accad. Italia 6, 119 (1934)
  
• sic_adsic:
  Average-density SIC. C. Legrand et al., J. Phys. B 35, 1115 (2002). Extension to the spinor case follows Tancogne-Dejean et al., J. Chem. Phys. 159, 224110 (2023)
  

Name VDW_TS_cutoff
Section Hamiltonian::XC
Type float
Default 10.0

Set the value of the cutoff (unit of length) for the VDW correction in periodic system in the Tkatchenko and Scheffler (vdw_ts) scheme only.

Name VDW_TS_damping
Section Hamiltonian::XC
Type float
Default 20.0

Set the value of the damping function (in unit of 1/length) steepness for the VDW correction in the Tkatchenko-Scheffler scheme. See Equation (12) of Phys. Rev. Lett. 102 073005 (2009).

Name VDW_TS_sr
Section Hamiltonian::XC
Type float
Default 0.94

Set the value of the sr parameter in the damping function of the VDW correction in the Tkatchenko-Scheffler scheme. See Equation (12) of Phys. Rev. Lett. 102 073005 (2009). This parameter depends on the xc functional used. The default value is 0.94, which holds for PBE. For PBE0, a value of 0.96 should be used.

Name VDWCorrection
Section Hamiltonian::XC
Type integer
Default no

(Experimental) This variable selects which van der Waals correction to apply to the correlation functional.

Options:

• none:
  No correction is applied.
  
• vdw_ts:
  The scheme of Tkatchenko and Scheffler, Phys. Rev. Lett. 102 073005 (2009).
  
• vdw_d3:
  The DFT-D3 scheme of S. Grimme, J. Antony, S. Ehrlich, and S. Krieg, J. Chem. Phys. 132, 154104 (2010).
  

Name VDWD3Functional
Section Hamiltonian::XC
Type string

(Experimental) You can use this variable to override the parametrization used by the DFT-D3 van deer Waals correction. Normally you need not set this variable, as the proper value will be selected by Octopus (if available).

This variable takes a string value, the valid values can be found in the source file ‘external_libs/dftd3/core.f90’. For example you can use:

VDWD3Functional = ‘pbe’

Name VDWSelfConsistent
Section Hamiltonian::XC
Type logical
Default yes

This variable controls whether the VDW correction is applied self-consistently, the default, or just as a correction to the total energy. This option only works with vdw_ts.

Name Xalpha
Section Hamiltonian::XC
Type float
Default 1.0

The parameter of the Slater X$\alpha$ functional. Applies only for XCFunctional = xc_lda_c_xalpha.

Name XCFunctional
Section Hamiltonian::XC
Type integer

Defines the exchange and correlation functionals to be used, specified as a sum of an exchange functional and a correlation functional, or a single exchange-correlation functional (e.g. hyb_gga_xc_pbeh). For more information on the functionals, see Libxc documentation. The list provided here is from libxc 6.2.2; if you have linked against a different libxc version, you may have a somewhat different set of available functionals. Note that kinetic-energy functionals are not supported.

The default functional will be selected by Octopus to be consistent with the pseudopotentials you are using. If you are not using pseudopotentials, Octopus cannot determine the functional used to generate the pseudopotential, or the pseudopotential functionals are inconsistent, Octopus will use the following defaults:

1D: lda_x_1d_soft + lda_c_1d_csc
2D: lda_x_2d + lda_c_2d_amgb
3D: lda_x + lda_c_pz_mod

Options:

• lda_x:
  Slater exchange
  
• lda_c_wigner:
  Wigner
  
• lda_c_rpa:
  Random Phase Approximation (RPA)
  
• lda_c_hl:
  Hedin & Lundqvist
  
• lda_c_gl:
  Gunnarson & Lundqvist
  
• lda_c_xalpha:
  Slater`s Xalpha
  
• lda_c_vwn:
  Vosko, Wilk & Nusair (VWN5)
  
• lda_c_vwn_rpa:
  Vosko, Wilk & Nusair (VWN5_RPA)
  
• lda_c_pz:
  Perdew & Zunger
  
• lda_c_pz_mod:
  Perdew & Zunger (Modified)
  
• lda_c_ob_pz:
  Ortiz & Ballone (PZ parametrization)
  
• lda_c_pw:
  Perdew & Wang
  
• lda_c_pw_mod:
  Perdew & Wang (modified)
  
• lda_c_ob_pw:
  Ortiz & Ballone (PW parametrization)
  
• lda_c_2d_amgb:
  AMGB (for 2D systems)
  
• lda_c_2d_prm:
  PRM (for 2D systems)
  
• lda_c_vbh:
  von Barth & Hedin
  
• lda_c_1d_csc:
  Casula, Sorella & Senatore
  
• lda_x_2d:
  Slater exchange
  
• lda_xc_teter93:
  Teter 93
  
• lda_x_1d_soft:
  Exchange in 1D for an soft-Coulomb interaction
  
• lda_c_ml1:
  Modified LSD (version 1) of Proynov and Salahub
  
• lda_c_ml2:
  Modified LSD (version 2) of Proynov and Salahub
  
• lda_c_gombas:
  Gombas
  
• lda_c_pw_rpa:
  Perdew & Wang (fit to the RPA energy)
  
• lda_c_1d_loos:
  P-F Loos correlation LDA
  
• lda_c_rc04:
  Ragot-Cortona
  
• lda_c_vwn_1:
  Vosko, Wilk & Nusair (VWN1)
  
• lda_c_vwn_2:
  Vosko, Wilk & Nusair (VWN2)
  
• lda_c_vwn_3:
  Vosko, Wilk & Nusair (VWN3)
  
• lda_c_vwn_4:
  Vosko, Wilk & Nusair (VWN4)
  
• gga_x_gam:
  Minnesota GAM exhange functional
  
• gga_c_gam:
  Minnesota GAM correlation functional
  
• gga_x_hcth_a:
  HCTH-A
  
• gga_x_ev93:
  Engel and Vosko
  
• hyb_mgga_x_dldf:
  Dispersionless Density Functional
  
• mgga_c_dldf:
  Dispersionless Density Functional
  
• gga_x_bcgp:
  Burke, Cancio, Gould, and Pittalis
  
• gga_c_acgga:
  acGGA, asymptotically corrected GGA correlation
  
• gga_x_lambda_oc2_n:
  lambda_OC2(N) version of PBE
  
• gga_x_b86_r:
  Revised Becke 86 with modified gradient correction
  
• mgga_xc_zlp:
  Zhao, Levy & Parr, Eq. (21)
  
• lda_xc_zlp:
  Zhao, Levy & Parr, Eq. (20)
  
• gga_x_lambda_ch_n:
  lambda_CH(N) version of PBE
  
• gga_x_lambda_lo_n:
  lambda_LO(N) version of PBE
  
• gga_x_hjs_b88_v2:
  HJS screened exchange B88 corrected version
  
• gga_c_q2d:
  Chiodo et al
  
• gga_x_q2d:
  Chiodo et al
  
• gga_x_pbe_mol:
  Reparametrized PBE by del Campo, Gazquez, Trickey & Vela
  
• gga_x_ak13:
  Armiento & Kuemmel 2013
  
• gga_x_lv_rpw86:
  Berland and Hyldgaard
  
• gga_x_pbe_tca:
  PBE revised by Tognetti et al
  
• gga_x_pbeint:
  PBE for hybrid interfaces
  
• gga_c_zpbeint:
  spin-dependent gradient correction to PBEint
  
• gga_c_pbeint:
  PBE for hybrid interfaces
  
• gga_c_zpbesol:
  spin-dependent gradient correction to PBEsol
  
• mgga_xc_otpss_d:
  oTPSS-D functional of Goerigk and Grimme
  
• gga_xc_opbe_d:
  oPBE-D functional of Goerigk and Grimme
  
• gga_xc_opwlyp_d:
  oPWLYP-D functional of Goerigk and Grimme
  
• gga_xc_oblyp_d:
  oBLYP-D functional of Goerigk and Grimme
  
• gga_x_vmt84_ge:
  VMT{8,4} with constraint satisfaction with mu = mu_GE
  
• gga_x_vmt84_pbe:
  VMT{8,4} with constraint satisfaction with mu = mu_PBE
  
• gga_x_vmt_ge:
  Vela, Medel, and Trickey with mu = mu_GE
  
• gga_x_vmt_pbe:
  Vela, Medel, and Trickey with mu = mu_PBE
  
• mgga_c_cs:
  Colle and Salvetti
  
• mgga_c_mn12_sx:
  Minnesota MN12-SX correlation functional
  
• mgga_c_mn12_l:
  Minnesota MN12-L correlation functional
  
• mgga_c_m11_l:
  Minnesota M11-L correlation functional
  
• mgga_c_m11:
  Minnesota M11 correlation functional
  
• mgga_c_m08_so:
  Minnesota M08-SO correlation functional
  
• mgga_c_m08_hx:
  Minnesota M08 correlation functional
  
• gga_c_n12_sx:
  Minnesota N12-SX correlation functional
  
• gga_c_n12:
  Minnesota N12 correlation functional
  
• hyb_gga_x_n12_sx:
  Minnesota N12-SX exchange functional
  
• gga_x_n12:
  Minnesota N12 exchange functional
  
• gga_c_regtpss:
  regularized TPSS correlation
  
• gga_c_op_xalpha:
  one-parameter progressive functional (Xalpha version)
  
• gga_c_op_g96:
  one-parameter progressive functional (G96 version)
  
• gga_c_op_pbe:
  one-parameter progressive functional (PBE version)
  
• gga_c_op_b88:
  one-parameter progressive functional (B88 version)
  
• gga_c_ft97:
  Filatov & Thiel correlation
  
• gga_c_spbe:
  PBE correlation to be used with the SSB exchange
  
• gga_x_ssb_sw:
  Swart, Sola and Bickelhaupt correction to PBE
  
• gga_x_ssb:
  Swart, Sola and Bickelhaupt
  
• gga_x_ssb_d:
  Swart, Sola and Bickelhaupt dispersion
  
• gga_xc_hcth_407p:
  HCTH/407+
  
• gga_xc_hcth_p76:
  HCTH p=7/6
  
• gga_xc_hcth_p14:
  HCTH p=1/4
  
• gga_xc_b97_gga1:
  Becke 97 GGA-1
  
• gga_c_hcth_a:
  HCTH-A
  
• gga_x_bpccac:
  BPCCAC (GRAC for the energy)
  
• gga_c_revtca:
  Tognetti, Cortona, Adamo (revised)
  
• gga_c_tca:
  Tognetti, Cortona, Adamo
  
• gga_x_pbe:
  Perdew, Burke & Ernzerhof
  
• gga_x_pbe_r:
  Revised PBE from Zhang & Yang
  
• gga_x_b86:
  Becke 86
  
• gga_x_b86_mgc:
  Becke 86 with modified gradient correction
  
• gga_x_b88:
  Becke 88
  
• gga_x_g96:
  Gill 96
  
• gga_x_pw86:
  Perdew & Wang 86
  
• gga_x_pw91:
  Perdew & Wang 91
  
• gga_x_optx:
  Handy & Cohen OPTX 01
  
• gga_x_dk87_r1:
  dePristo & Kress 87 version R1
  
• gga_x_dk87_r2:
  dePristo & Kress 87 version R2
  
• gga_x_lg93:
  Lacks & Gordon 93
  
• gga_x_ft97_a:
  Filatov & Thiel 97 (version A)
  
• gga_x_ft97_b:
  Filatov & Thiel 97 (version B)
  
• gga_x_pbe_sol:
  Perdew, Burke & Ernzerhof SOL
  
• gga_x_rpbe:
  Hammer, Hansen, and Norskov
  
• gga_x_wc:
  Wu & Cohen
  
• gga_x_mpw91:
  mPW91 of Adamo & Barone
  
• gga_x_am05:
  Armiento & Mattsson 05
  
• gga_x_pbea:
  Madsen 07
  
• gga_x_mpbe:
  Adamo & Barone modification to PBE
  
• gga_x_xpbe:
  Extended PBE by Xu & Goddard III
  
• gga_x_2d_b86_mgc:
  Becke 86 with modified gradient correction for 2D
  
• gga_x_bayesian:
  Bayesian best fit for the enhancement factor
  
• gga_x_pbe_jsjr:
  Reparametrized PBE by Pedroza, Silva & Capelle
  
• gga_x_2d_b88:
  Becke 88 in 2D
  
• gga_x_2d_b86:
  Becke 86 in 2D
  
• gga_x_2d_pbe:
  Perdew, Burke & Ernzerhof in 2D
  
• gga_c_pbe:
  Perdew, Burke & Ernzerhof
  
• gga_c_lyp:
  Lee, Yang & Parr
  
• gga_c_p86:
  Perdew 86
  
• gga_c_pbe_sol:
  Perdew, Burke & Ernzerhof SOL
  
• gga_c_pw91:
  Perdew & Wang 91
  
• gga_c_am05:
  Armiento & Mattsson 05
  
• gga_c_xpbe:
  Extended PBE by Xu & Goddard III
  
• gga_c_lm:
  Langreth & Mehl
  
• gga_c_pbe_jrgx:
  Reparametrized PBE by Pedroza, Silva & Capelle
  
• gga_x_optb88_vdw:
  opt-Becke 88 for vdW
  
• gga_x_pbek1_vdw:
  Reparametrized PBE for vdW
  
• gga_x_optpbe_vdw:
  Reparametrized PBE for vdW
  
• gga_x_rge2:
  Regularized PBE
  
• gga_c_rge2:
  Regularized PBE
  
• gga_x_rpw86:
  Refitted Perdew & Wang 86
  
• gga_x_kt1:
  Exchange part of Keal and Tozer version 1
  
• gga_xc_kt2:
  Keal and Tozer, version 2
  
• gga_c_wl:
  Wilson & Levy
  
• gga_c_wi:
  Wilson & Ivanov
  
• gga_x_mb88:
  Modified Becke 88 for proton transfer
  
• gga_x_sogga:
  Second-order generalized gradient approximation
  
• gga_x_sogga11:
  Second-order generalized gradient approximation 2011
  
• gga_c_sogga11:
  Second-order generalized gradient approximation 2011
  
• gga_c_wi0:
  Wilson & Ivanov initial version
  
• gga_xc_th1:
  Tozer and Handy v. 1
  
• gga_xc_th2:
  Tozer and Handy v. 2
  
• gga_xc_th3:
  Tozer and Handy v. 3
  
• gga_xc_th4:
  Tozer and Handy v. 4
  
• gga_x_c09x:
  C09x to be used with the VdW of Rutgers-Chalmers
  
• gga_c_sogga11_x:
  To be used with HYB_GGA_X_SOGGA11_X
  
• gga_x_lb:
  van Leeuwen & Baerends
  
• gga_xc_hcth_93:
  HCTH/93
  
• gga_xc_hcth_120:
  HCTH/120
  
• gga_xc_hcth_147:
  HCTH/147
  
• gga_xc_hcth_407:
  HCTH/407
  
• gga_xc_edf1:
  EDF1
  
• gga_xc_xlyp:
  XLYP
  
• gga_xc_kt1:
  Keal and Tozer, version 1
  
• gga_x_lspbe:
  lsPBE, a PW91-like modification of PBE exchange
  
• gga_x_lsrpbe:
  lsRPBE, a PW91-like modification of RPBE
  
• gga_xc_b97_d:
  Becke 97-D
  
• gga_x_optb86b_vdw:
  Becke 86 reoptimized for use with vdW functional of Dion et al
  
• mgga_c_revm11:
  Revised Minnesota M11 correlation functional
  
• gga_xc_pbe1w:
  PBE1W
  
• gga_xc_mpwlyp1w:
  mPWLYP1w
  
• gga_xc_pbelyp1w:
  PBELYP1W
  
• gga_c_acggap:
  acGGA+, asymptotically corrected GGA correlation+
  
• hyb_lda_xc_lda0:
  LDA hybrid exchange (LDA0)
  
• hyb_lda_xc_cam_lda0:
  CAM version of LDA0
  
• gga_x_b88_6311g:
  Becke 88 reoptimized with the 6-311G** basis set
  
• gga_x_ncap:
  Nearly correct asymptotic potential
  
• gga_xc_ncap:
  NCAP exchange + P86 correlation
  
• gga_x_lbm:
  van Leeuwen & Baerends modified
  
• gga_x_ol2:
  Exchange form based on Ou-Yang and Levy v.2
  
• gga_x_apbe:
  mu fixed from the semiclassical neutral atom
  
• gga_c_apbe:
  mu fixed from the semiclassical neutral atom
  
• gga_x_htbs:
  Haas, Tran, Blaha, and Schwarz
  
• gga_x_airy:
  Constantin et al based on the Airy gas
  
• gga_x_lag:
  Local Airy Gas
  
• gga_xc_mohlyp:
  Functional for organometallic chemistry
  
• gga_xc_mohlyp2:
  Functional for barrier heights
  
• gga_xc_th_fl:
  Tozer and Handy v. FL
  
• gga_xc_th_fc:
  Tozer and Handy v. FC
  
• gga_xc_th_fcfo:
  Tozer and Handy v. FCFO
  
• gga_xc_th_fco:
  Tozer and Handy v. FCO
  
• gga_c_optc:
  Optimized correlation functional of Cohen and Handy
  
• mgga_x_lta:
  Local tau approximation
  
• mgga_x_tpss:
  Tao, Perdew, Staroverov & Scuseria
  
• mgga_x_m06_l:
  Minnesota M06-L exchange functional
  
• mgga_x_gvt4:
  GVT4 (X part of VSXC)
  
• mgga_x_tau_hcth:
  tau-HCTH from Boese and Handy
  
• mgga_x_br89:
  Becke-Roussel 89, gamma = 0.8
  
• mgga_x_bj06:
  Becke & Johnson 06
  
• mgga_x_tb09:
  Tran & Blaha 09
  
• mgga_x_rpp09:
  Rasanen, Pittalis & Proetto 09
  
• mgga_x_2d_prhg07:
  Pittalis-Rasanen-Helbig-Gross 2007
  
• mgga_x_2d_prhg07_prp10:
  PRHG07 with Pittalis-Rasanen-Proetto 2010 correction
  
• mgga_x_revtpss:
  revised Tao, Perdew, Staroverov & Scuseria
  
• mgga_x_pkzb:
  Perdew, Kurth, Zupan, and Blaha
  
• mgga_x_br89_1:
  Becke-Roussel 89, gamma = 1.0
  
• gga_x_ecmv92:
  Engel, Chevary, Macdonald and Vosko
  
• gga_c_pbe_vwn:
  Perdew, Burke & Ernzerhof based on VWN correlation
  
• gga_c_p86_ft:
  Perdew 86 with more accurate value for ftilde
  
• mgga_x_ms0:
  MS exchange of Sun, Xiao, and Ruzsinszky
  
• mgga_x_ms1:
  MS1 exchange of Sun, et al
  
• mgga_x_ms2:
  MS2 exchange of Sun, et al
  
• hyb_mgga_x_ms2h:
  MS2 hybrid exchange of Sun, et al
  
• mgga_x_th:
  Tsuneda and Hirao
  
• mgga_x_m11_l:
  Minnesota M11-L exchange functional
  
• mgga_x_mn12_l:
  Minnesota MN12-L exchange functional
  
• mgga_x_ms2_rev:
  MS2 exchange of Sun, et al with revised value for c
  
• mgga_xc_cc06:
  Cancio and Chou 2006
  
• mgga_x_mk00:
  Exchange for accurate virtual orbital energies
  
• mgga_c_tpss:
  Tao, Perdew, Staroverov & Scuseria
  
• mgga_c_vsxc:
  VSXC (correlation part)
  
• mgga_c_m06_l:
  Minnesota M06-L correlation functional
  
• mgga_c_m06_hf:
  Minnesota M06-HF correlation functional
  
• mgga_c_m06:
  Minnesota M06 correlation functional
  
• mgga_c_m06_2x:
  Minnesota M06-2X correlation functional
  
• mgga_c_m05:
  Minnesota M05 correlation functional
  
• mgga_c_m05_2x:
  Minnesota M05-2X correlation functional
  
• mgga_c_pkzb:
  Perdew, Kurth, Zupan, and Blaha
  
• mgga_c_bc95:
  Becke correlation 95
  
• mgga_c_revtpss:
  revised TPSS correlation
  
• mgga_xc_tpsslyp1w:
  TPSSLYP1W
  
• mgga_x_mk00b:
  Exchange for accurate virtual orbital energies (v. B)
  
• mgga_x_bloc:
  functional with balanced localization
  
• mgga_x_modtpss:
  Modified Tao, Perdew, Staroverov & Scuseria
  
• gga_c_pbeloc:
  Semilocal dynamical correlation
  
• mgga_c_tpssloc:
  Semilocal dynamical correlation
  
• hyb_mgga_x_mn12_sx:
  Minnesota MN12-SX hybrid exchange functional
  
• mgga_x_mbeef:
  mBEEF exchange
  
• mgga_x_mbeefvdw:
  mBEEF-vdW exchange
  
• mgga_c_tm:
  Tao and Mo 2016 correlation
  
• gga_c_p86vwn:
  Perdew 86 based on VWN5 correlation
  
• gga_c_p86vwn_ft:
  Perdew 86 based on VWN5 correlation, with more accurate value for ftilde
  
• mgga_xc_b97m_v:
  B97M-V exchange-correlation functional
  
• gga_xc_vv10:
  Vydrov and Van Voorhis
  
• mgga_x_jk:
  Jemmer-Knowles meta-GGA exchange
  
• mgga_x_mvs:
  MVS exchange of Sun, Perdew, and Ruzsinszky
  
• gga_c_pbefe:
  PBE for formation energies
  
• lda_xc_ksdt:
  Karasiev, Sjostrom, Dufty & Trickey
  
• mgga_x_mn15_l:
  Minnesota MN15-L exchange functional
  
• mgga_c_mn15_l:
  Minnesota MN15-L correlation functional
  
• gga_c_op_pw91:
  one-parameter progressive functional (PW91 version)
  
• mgga_x_scan:
  SCAN exchange of Sun, Ruzsinszky, and Perdew
  
• hyb_mgga_x_scan0:
  SCAN hybrid exchange (SCAN0)
  
• gga_x_pbefe:
  PBE for formation energies
  
• hyb_gga_xc_b97_1p:
  version of B97 by Cohen and Handy
  
• mgga_c_scan:
  SCAN correlation of Sun, Ruzsinszky, and Perdew
  
• hyb_mgga_x_mn15:
  Minnesota MN15 hybrid exchange functional
  
• mgga_c_mn15:
  Minnesota MN15 correlation functional
  
• gga_x_cap:
  Correct Asymptotic Potential
  
• gga_x_eb88:
  Non-empirical (excogitated) B88 functional of Becke and Elliott
  
• gga_c_pbe_mol:
  Reparametrized PBE by del Campo, Gazquez, Trickey & Vela
  
• hyb_gga_xc_pbe_mol0:
  PBEmol0
  
• hyb_gga_xc_pbe_sol0:
  PBEsol0
  
• hyb_gga_xc_pbeb0:
  PBEbeta0
  
• hyb_gga_xc_pbe_molb0:
  PBEmolbeta0
  
• hyb_mgga_x_bmk:
  Boese-Martin for kinetics
  
• gga_c_bmk:
  Boese-Martin correlation for kinetics
  
• gga_c_tau_hcth:
  correlation part of tau-hcth
  
• hyb_mgga_x_tau_hcth:
  Hybrid version of tau-HCTH
  
• gga_c_hyb_tau_hcth:
  correlation part of hyb-tau-hcth
  
• mgga_x_b00:
  Becke 2000
  
• gga_x_beefvdw:
  BEEF-vdW exchange
  
• gga_xc_beefvdw:
  BEEF-vdW exchange-correlation
  
• lda_c_chachiyo:
  Chachiyo simple 2 parameter correlation
  
• mgga_xc_hle17:
  high local exchange 2017
  
• lda_c_lp96:
  Liu-Parr correlation
  
• hyb_gga_xc_pbe50:
  PBE50
  
• gga_x_pbetrans:
  Gradient-regulated connection-based correction for the PBE exchange
  
• mgga_c_scan_rvv10:
  SCAN + rVV10 correlation
  
• mgga_x_revm06_l:
  Minnesota revM06-L exchange functional
  
• mgga_c_revm06_l:
  Minnesota revM06-L correlation functional
  
• hyb_mgga_x_m08_hx:
  Minnesota M08-HX hybrid exchange functional
  
• hyb_mgga_x_m08_so:
  Minnesota M08-SO hybrid exchange functional
  
• hyb_mgga_x_m11:
  Minnesota M11 hybrid exchange functional
  
• gga_x_chachiyo:
  Chachiyo exchange
  
• mgga_x_rtpss:
  TPSS for surface adsorption
  
• mgga_x_ms2b:
  MS2beta exchange of Furness and Sun
  
• mgga_x_ms2bs:
  MS2beta* exchange of Furness and Sun
  
• mgga_x_mvsb:
  MVSbeta exchange by Furness and Sun
  
• mgga_x_mvsbs:
  MVSbeta* exchange by Furness and Sun
  
• hyb_mgga_x_revm11:
  Revised Minnesota M11 hybrid exchange functional
  
• hyb_mgga_x_revm06:
  Revised Minnesota M06 hybrid exchange functional
  
• mgga_c_revm06:
  Revised Minnesota M06 correlation functional
  
• lda_c_chachiyo_mod:
  Chachiyo simple 2 parameter correlation with modified spin scaling
  
• lda_c_karasiev_mod:
  Karasiev reparameterization of Chachiyo
  
• gga_c_chachiyo:
  Chachiyo simple GGA correlation
  
• hyb_mgga_x_m06_sx:
  Minnesota M06-SX short-range hybrid exchange functional
  
• mgga_c_m06_sx:
  Minnesota M06-SX correlation functional
  
• gga_x_revssb_d:
  Revised Swart, Sola and Bickelhaupt dispersion
  
• gga_c_ccdf:
  ccDF: coupled-cluster motivated density functional
  
• hyb_gga_xc_hflyp:
  HF + LYP correlation
  
• hyb_gga_xc_b3p86_nwchem:
  B3P86, NWChem version
  
• gga_x_pw91_mod:
  PW91, alternate version with more digits
  
• lda_c_w20:
  Xie, Wu, and Zhao interpolation ansatz without fitting parameters
  
• lda_xc_corrksdt:
  Corrected KSDT by Karasiev, Dufty and Trickey
  
• mgga_x_ft98:
  Filatov and Thiel 1998 meta-GGA exchange
  
• gga_x_pbe_mod:
  Perdew, Burke & Ernzerhof with less precise value for beta
  
• gga_x_pbe_gaussian:
  Perdew, Burke & Ernzerhof with parameter values used in Gaussian
  
• gga_c_pbe_gaussian:
  Perdew, Burke & Ernzerhof with parameters from Gaussian
  
• mgga_c_tpss_gaussian:
  Tao, Perdew, Staroverov & Scuseria with parameters from Gaussian
  
• gga_x_ncapr:
  Nearly correct asymptotic potential revised
  
• hyb_gga_xc_relpbe0:
  relPBE0 a.k.a. relPBE: PBE0 refitted for actinide compounds
  
• gga_xc_b97_3c:
  Becke 97-3c by Grimme et. al.
  
• mgga_c_cc:
  Self-interaction corrected correlation functional by Schmidt et al
  
• mgga_c_ccalda:
  Iso-orbital corrected LDA correlation by Lebeda et al
  
• hyb_mgga_xc_br3p86:
  BR3P86 hybrid meta-GGA from Neumann and Handy
  
• hyb_gga_xc_case21:
  CASE21: Constrained And Smoothed semi-Empirical 2021 functional
  
• mgga_c_rregtm:
  Revised regTM correlation by Jana et al
  
• hyb_gga_xc_pbe_2x:
  PBE-2X: PBE0 with 56% exact exchange
  
• hyb_gga_xc_pbe38:
  PBE38: PBE0 with 3/8 = 37.5% exact exchange
  
• hyb_gga_xc_b3lyp3:
  B3LYP with VWN functional 3 instead of RPA
  
• hyb_gga_xc_cam_o3lyp:
  CAM-O3LYP
  
• hyb_mgga_xc_tpss0:
  TPSS0 with 25% exact exchange
  
• mgga_c_b94:
  Becke 1994 meta-GGA correlation
  
• hyb_mgga_xc_b94_hyb:
  Becke 1994 hybrid meta-GGA
  
• hyb_gga_xc_wb97x_d3:
  wB97X-D3 range-separated functional
  
• hyb_gga_xc_lc_blyp:
  LC version of BLYP
  
• hyb_gga_xc_b3pw91:
  The original (ACM, B3PW91) hybrid of Becke
  
• hyb_gga_xc_b3lyp:
  B3LYP
  
• hyb_gga_xc_b3p86:
  B3P86
  
• hyb_gga_xc_o3lyp:
  O3LYP
  
• hyb_gga_xc_mpw1k:
  mPW1K
  
• hyb_gga_xc_pbeh:
  PBEH (PBE0)
  
• hyb_gga_xc_b97:
  Becke 97
  
• hyb_gga_xc_b97_1:
  Becke 97-1
  
• hyb_gga_xc_apf:
  APF hybrid functional
  
• hyb_gga_xc_b97_2:
  Becke 97-2
  
• hyb_gga_xc_x3lyp:
  X3LYP
  
• hyb_gga_xc_b1wc:
  B1WC
  
• hyb_gga_xc_b97_k:
  Boese-Martin for Kinetics
  
• hyb_gga_xc_b97_3:
  Becke 97-3
  
• hyb_gga_xc_mpw3pw:
  MPW3PW of Adamo & Barone
  
• hyb_gga_xc_b1lyp:
  B1LYP
  
• hyb_gga_xc_b1pw91:
  B1PW91
  
• hyb_gga_xc_mpw1pw:
  mPW1PW
  
• hyb_gga_xc_mpw3lyp:
  MPW3LYP
  
• hyb_gga_xc_sb98_1a:
  SB98 (1a)
  
• hyb_gga_xc_sb98_1b:
  SB98 (1b)
  
• hyb_gga_xc_sb98_1c:
  SB98 (1c)
  
• hyb_gga_xc_sb98_2a:
  SB98 (2a)
  
• hyb_gga_xc_sb98_2b:
  SB98 (2b)
  
• hyb_gga_xc_sb98_2c:
  SB98 (2c)
  
• hyb_gga_x_sogga11_x:
  Hybrid based on SOGGA11 form
  
• hyb_gga_xc_hse03:
  HSE03
  
• hyb_gga_xc_hse06:
  HSE06
  
• hyb_gga_xc_hjs_pbe:
  HJS hybrid screened exchange PBE version
  
• hyb_gga_xc_hjs_pbe_sol:
  HJS hybrid screened exchange PBE_SOL version
  
• hyb_gga_xc_hjs_b88:
  HJS hybrid screened exchange B88 version
  
• hyb_gga_xc_hjs_b97x:
  HJS hybrid screened exchange B97x version
  
• hyb_gga_xc_cam_b3lyp:
  CAM version of B3LYP
  
• hyb_gga_xc_tuned_cam_b3lyp:
  CAM version of B3LYP, tuned for excitations and properties
  
• hyb_gga_xc_bhandh:
  BHandH i.e. BHLYP
  
• hyb_gga_xc_bhandhlyp:
  BHandHLYP
  
• hyb_gga_xc_mb3lyp_rc04:
  B3LYP with RC04 LDA
  
• hyb_mgga_x_m05:
  Minnesota M05 hybrid exchange functional
  
• hyb_mgga_x_m05_2x:
  Minnesota M05-2X hybrid exchange functional
  
• hyb_mgga_xc_b88b95:
  Mixture of B88 with BC95 (B1B95)
  
• hyb_mgga_xc_b86b95:
  Mixture of B86 with BC95
  
• hyb_mgga_xc_pw86b95:
  Mixture of PW86 with BC95
  
• hyb_mgga_xc_bb1k:
  Mixture of B88 with BC95 from Zhao and Truhlar
  
• hyb_mgga_x_m06_hf:
  Minnesota M06-HF hybrid exchange functional
  
• hyb_mgga_xc_mpw1b95:
  Mixture of mPW91 with BC95 from Zhao and Truhlar
  
• hyb_mgga_xc_mpwb1k:
  Mixture of mPW91 with BC95 for kinetics
  
• hyb_mgga_xc_x1b95:
  Mixture of X with BC95
  
• hyb_mgga_xc_xb1k:
  Mixture of X with BC95 for kinetics
  
• hyb_mgga_x_m06:
  Minnesota M06 hybrid exchange functional
  
• hyb_mgga_x_m06_2x:
  Minnesota M06-2X hybrid exchange functional
  
• hyb_mgga_xc_pw6b95:
  Mixture of PW91 with BC95 from Zhao and Truhlar
  
• hyb_mgga_xc_pwb6k:
  Mixture of PW91 with BC95 from Zhao and Truhlar for kinetics
  
• hyb_gga_xc_mpwlyp1m:
  MPW with 1 par. for metals/LYP
  
• hyb_gga_xc_revb3lyp:
  Revised B3LYP
  
• hyb_gga_xc_camy_blyp:
  CAMY version of BLYP
  
• hyb_gga_xc_pbe0_13:
  PBE0-1/3
  
• hyb_mgga_xc_tpssh:
  TPSSh
  
• hyb_mgga_xc_revtpssh:
  revTPSSh
  
• hyb_gga_xc_b3lyps:
  B3LYP*
  
• hyb_gga_xc_qtp17:
  Global hybrid for vertical ionization potentials
  
• hyb_gga_xc_b3lyp_mcm1:
  B3LYP-MCM1
  
• hyb_gga_xc_b3lyp_mcm2:
  B3LYP-MCM2
  
• hyb_gga_xc_wb97:
  wB97 range-separated functional
  
• hyb_gga_xc_wb97x:
  wB97X range-separated functional
  
• hyb_gga_xc_lrc_wpbeh:
  Long-range corrected short-range hybrid PBE (LRC-wPBEh) by Rohrdanz, Martins and Herbert
  
• hyb_gga_xc_wb97x_v:
  wB97X-V range-separated functional
  
• hyb_gga_xc_lcy_pbe:
  LCY version of PBE
  
• hyb_gga_xc_lcy_blyp:
  LCY version of BLYP
  
• hyb_gga_xc_lc_vv10:
  Vydrov and Van Voorhis
  
• hyb_gga_xc_camy_b3lyp:
  CAMY version of B3LYP
  
• hyb_gga_xc_wb97x_d:
  wB97X-D range-separated functional
  
• hyb_gga_xc_hpbeint:
  hPBEint
  
• hyb_gga_xc_lrc_wpbe:
  Long-range corrected PBE (LRC-wPBE) by Rohrdanz, Martins and Herbert
  
• hyb_mgga_x_mvsh:
  MVSh hybrid exchange functional
  
• hyb_gga_xc_b3lyp5:
  B3LYP with VWN functional 5 instead of RPA
  
• hyb_gga_xc_edf2:
  EDF2
  
• hyb_gga_xc_cap0:
  Correct Asymptotic Potential hybrid
  
• hyb_gga_xc_lc_wpbe:
  Long-range corrected PBE (LC-wPBE) by Vydrov and Scuseria
  
• hyb_gga_xc_hse12:
  HSE12
  
• hyb_gga_xc_hse12s:
  HSE12 (short-range version)
  
• hyb_gga_xc_hse_sol:
  HSEsol
  
• hyb_gga_xc_cam_qtp_01:
  CAM-B3LYP retuned using ionization potentials of water
  
• hyb_gga_xc_mpw1lyp:
  mPW1LYP
  
• hyb_gga_xc_mpw1pbe:
  mPW1PBE
  
• hyb_gga_xc_kmlyp:
  Kang-Musgrave hybrid
  
• hyb_gga_xc_lc_wpbe_whs:
  Long-range corrected PBE (LC-wPBE) by Weintraub, Henderson and Scuseria
  
• hyb_gga_xc_lc_wpbeh_whs:
  Long-range corrected short-range hybrid PBE (LC-wPBE) by Weintraub, Henderson and Scuseria
  
• hyb_gga_xc_lc_wpbe08_whs:
  Long-range corrected PBE (LC-wPBE) by Weintraub, Henderson and Scuseria
  
• hyb_gga_xc_lc_wpbesol_whs:
  Long-range corrected PBE (LC-wPBE) by Weintraub, Henderson and Scuseria
  
• hyb_gga_xc_cam_qtp_00:
  CAM-B3LYP retuned using ionization potentials of water
  
• hyb_gga_xc_cam_qtp_02:
  CAM-B3LYP retuned using ionization potentials of water
  
• hyb_gga_xc_lc_qtp:
  CAM-B3LYP retuned using ionization potentials of water
  
• mgga_x_rscan:
  Regularized SCAN exchange by Bartok and Yates
  
• mgga_c_rscan:
  Regularized SCAN correlation by Bartok and Yates
  
• gga_x_s12g:
  Swart 2012 GGA exchange
  
• hyb_gga_x_s12h:
  Swart 2012 hybrid exchange
  
• mgga_x_r2scan:
  Re-regularized SCAN exchange by Furness et al
  
• mgga_c_r2scan:
  Re-regularized SCAN correlation by Furness et al
  
• hyb_gga_xc_blyp35:
  BLYP35
  
• gga_x_wpbeh:
  short-range part of the PBE (default w=0 gives PBEh)
  
• gga_x_hjs_pbe:
  HJS screened exchange PBE version
  
• gga_x_hjs_pbe_sol:
  HJS screened exchange PBE_SOL version
  
• gga_x_hjs_b88:
  HJS screened exchange B88 version
  
• gga_x_hjs_b97x:
  HJS screened exchange B97x version
  
• gga_x_ityh:
  Short-range recipe for B88 functional - erf
  
• gga_x_sfat:
  Short-range recipe for B88 functional - Yukawa
  
• hyb_mgga_xc_wb97m_v:
  wB97M-V exchange-correlation functional
  
• lda_x_rel:
  Slater exchange with relativistic corrections
  
• gga_x_sg4:
  Semiclassical GGA at fourth order
  
• gga_c_sg4:
  Semiclassical GGA at fourth order
  
• gga_x_gg99:
  Gilbert and Gill 1999
  
• lda_xc_1d_ehwlrg_1:
  LDA constructed from slab-like systems of 1 electron
  
• lda_xc_1d_ehwlrg_2:
  LDA constructed from slab-like systems of 2 electrons
  
• lda_xc_1d_ehwlrg_3:
  LDA constructed from slab-like systems of 3 electrons
  
• gga_x_pbepow:
  PBE power
  
• mgga_x_tm:
  Tao and Mo 2016 exchange
  
• mgga_x_vt84:
  meta-GGA version of VT{8,4} GGA
  
• mgga_x_sa_tpss:
  TPSS with correct surface asymptotics
  
• gga_x_kgg99:
  Gilbert and Gill 1999 (mixed)
  
• gga_xc_hle16:
  high local exchange 2016
  
• lda_x_erf:
  Short-range LDA exchange with error function kernel (erfc)
  
• lda_xc_lp_a:
  Lee-Parr reparametrization A
  
• lda_xc_lp_b:
  Lee-Parr reparametrization B
  
• lda_x_rae:
  Rae self-energy corrected exchange
  
• lda_c_mcweeny:
  McWeeny 76
  
• lda_c_br78:
  Brual & Rothstein 78
  
• gga_c_scan_e0:
  GGA component of SCAN
  
• lda_c_pk09:
  Proynov and Kong 2009
  
• gga_c_gapc:
  GapC
  
• gga_c_gaploc:
  Gaploc
  
• gga_c_zvpbeint:
  another spin-dependent correction to PBEint
  
• gga_c_zvpbesol:
  another spin-dependent correction to PBEsol
  
• gga_c_tm_lyp:
  Takkar and McCarthy reparametrization
  
• gga_c_tm_pbe:
  Thakkar and McCarthy reparametrization
  
• gga_c_w94:
  Wilson 94 (Eq. 25)
  
• mgga_c_kcis:
  Krieger, Chen, Iafrate, and Savin
  
• hyb_mgga_xc_b0kcis:
  Hybrid based on KCIS
  
• mgga_xc_lp90:
  Lee & Parr, Eq. (56)
  
• gga_c_cs1:
  A dynamical correlation functional
  
• hyb_mgga_xc_mpw1kcis:
  MPW1KCIS for barrier heights
  
• hyb_mgga_xc_mpwkcis1k:
  MPWKCIS1K for barrier heights
  
• hyb_mgga_xc_pbe1kcis:
  PBE1KCIS for binding energies
  
• hyb_mgga_xc_tpss1kcis:
  TPSS1KCIS for thermochemistry and kinetics
  
• gga_x_b88m:
  Becke 88 reoptimized to be used with tau1
  
• mgga_c_b88:
  Meta-GGA correlation by Becke
  
• hyb_gga_xc_b5050lyp:
  B5050LYP
  
• lda_c_ow_lyp:
  Wigner with corresponding LYP parameters
  
• lda_c_ow:
  Optimized Wigner
  
• mgga_x_gx:
  GX functional of Loos
  
• mgga_x_pbe_gx:
  PBE-GX functional of Loos
  
• lda_xc_gdsmfb:
  Groth, Dornheim, Sjostrom, Malone, Foulkes, Bonitz
  
• lda_c_gk72:
  Gordon and Kim 1972
  
• lda_c_karasiev:
  Karasiev reparameterization of Chachiyo
  
• mgga_x_revscan:
  revised SCAN
  
• mgga_c_revscan:
  revised SCAN
  
• hyb_mgga_x_revscan0:
  revised SCAN hybrid exchange (SCAN0)
  
• mgga_c_scan_vv10:
  SCAN + VV10 correlation
  
• mgga_c_revscan_vv10:
  REVSCAN + VV10 correlation
  
• mgga_x_br89_explicit:
  Becke-Roussel 89 with an explicit inversion of x(y), gamma = 0.8
  
• gga_xc_kt3:
  Keal and Tozer, version 3
  
• hyb_lda_xc_bn05:
  Baer and Neuhauser, gamma=1
  
• hyb_gga_xc_lb07:
  Livshits and Baer, empirical functional also used for IP tuning
  
• lda_c_pmgb06:
  Long-range LDA correlation functional
  
• hyb_mgga_xc_b98:
  Becke 98
  
• lda_xc_tih:
  Neural network LDA from Tozer et al
  
• lda_x_1d_exponential:
  Exchange in 1D for an exponentially screened interaction
  
• gga_x_sfat_pbe:
  Short-range recipe for PBE functional - Yukawa
  
• mgga_x_br89_explicit_1:
  Becke-Roussel 89 with an explicit inversion of x(y), gamma = 1.0
  
• mgga_x_regtpss:
  Regularized TPSS
  
• gga_x_fd_lb94:
  Functional derivative recovered from the stray LB94 potential
  
• gga_x_fd_revlb94:
  Revised FD_LB94
  
• gga_c_zvpbeloc:
  PBEloc variation with enhanced compatibility with exact exchange
  
• hyb_gga_xc_apbe0:
  Hybrid based on APBE
  
• hyb_gga_xc_hapbe:
  Hybrid based in APBE and zvPBEloc
  
• mgga_x_2d_js17:
  JS17 meta-GGA for 2D
  
• hyb_gga_xc_rcam_b3lyp:
  Similar to CAM-B3LYP, but trying to reduce the many-electron self-interaction
  
• hyb_gga_xc_wc04:
  hybrid fitted to carbon NMR shifts
  
• hyb_gga_xc_wp04:
  hybrid fitted to proton NMR shifts
  
• hyb_gga_xc_camh_b3lyp:
  CAM version of B3LYP, tuned for TDDFT
  
• hyb_gga_xc_whpbe0:
  Long-range corrected short-range hybrid PBE (whPBE0) by Shao et al
  
• gga_x_ityh_optx:
  Short-range recipe for OPTX functional
  
• gga_x_ityh_pbe:
  Short-range recipe for PBE functional
  
• gga_c_lypr:
  Short-range LYP by Ai, Fang, and Su
  
• hyb_gga_xc_lc_blyp_ea:
  LC version of BLYP for electron affinities
  
• mgga_x_regtm:
  Regularized Tao and Mo exchange
  
• hyb_gga_xc_lc_bop:
  LC version of B88
  
• hyb_gga_xc_lc_pbeop:
  LC version of PBE
  
• mgga_c_kcisk:
  Krieger, Chen, and Kurth
  
• hyb_gga_xc_lc_blypr:
  LC version of BLYP with correlation only in the short range
  
• hyb_gga_xc_mcam_b3lyp:
  Modified CAM-B3LYP by Day, Nguyen and Pachter
  
• lda_x_yukawa:
  Short-range LDA exchange with Yukawa attenuation
  
• mgga_c_r2scan01:
  Re-regularized SCAN correlation with larger value for eta
  
• mgga_c_rmggac:
  Revised correlation energy for MGGAC exchange functional
  
• mgga_x_mcml:
  MCML exchange
  
• mgga_x_r2scan01:
  Re-regularized SCAN exchange by Furness et al with larger value for eta
  
• hyb_gga_x_cam_s12g:
  Swart 2012 range-separated hybrid GGA exchange
  
• hyb_gga_x_cam_s12h:
  Swart 2012 range-separated hybrid GGA exchange
  
• mgga_x_rppscan:
  r++SCAN: rSCAN with uniform density limit and coordinate scaling behavior
  
• mgga_c_rppscan:
  r++SCAN: rSCAN with uniform density limit and coordinate scaling behavior
  
• mgga_x_r4scan:
  r$^{4}$SCAN, a functional that satisfies the same exact constraints that SCAN does
  
• mgga_x_vcml:
  Exchange part of VCML-rVV10 by Trepte and Voss
  
• mgga_xc_vcml_rvv10:
  VCML-rVV10 by Trepte and Voss
  
• hyb_mgga_xc_gas22:
  Google Accelerated Science 22
  
• hyb_mgga_xc_r2scanh:
  r2SCANh: r2SCAN hybrid like TPSSh with 10% exact exchange
  
• hyb_mgga_xc_r2scan0:
  r2SCAN0: r2SCAN hybrid like PBE0 with 25% exact exchange
  
• hyb_mgga_xc_r2scan50:
  r2SCAN50: r2SCAN hybrid like PBE50 with 50% exact exchange
  
• hyb_gga_xc_cam_pbeh:
  CAM hybrid screened exchange PBE version
  
• hyb_gga_xc_camy_pbeh:
  CAMY hybrid screened exchange PBE version
  
• lda_c_upw92:
  Ruggeri, Rios, and Alavi unrestricted fit
  
• lda_c_rpw92:
  Ruggeri, Rios, and Alavi restricted fit
  
• mgga_x_tlda:
  LDA-type exchange with tau-dependent potential
  
• mgga_x_edmgga:
  Tao 2001
  
• mgga_x_gdme_nv:
  Generalized density-matrix with a=1/2
  
• mgga_x_rlda:
  Reparametrized local-density approximation
  
• mgga_x_gdme_0:
  Generalized density-matrix with a=0
  
• mgga_x_gdme_kos:
  Generalized density-matrix with a=0.00638
  
• mgga_x_gdme_vt:
  Varied-terms (VT) mGGA of Koehl, Odom, and Scuseria
  
• lda_x_sloc:
  simple local model for Slater potential
  
• mgga_x_revtm:
  revised Tao and Mo 2016 exchange
  
• mgga_c_revtm:
  revised Tao and Mo 2016 exchange
  
• hyb_mgga_xc_edmggah:
  EDMGGA hybrid
  
• mgga_x_mbrxc_bg:
  Modified Becke-Roussel for band gaps - cuspless hole
  
• mgga_x_mbrxh_bg:
  Modified Becke-Roussel for band gaps - hydrogen hole
  
• mgga_x_hlta:
  Half-and-half meta-LDAized LDA exchange by Lehtola and Marques
  
• mgga_c_hltapw:
  Half-and-half meta-LDAized PW correlation by Lehtola and Marques
  
• mgga_x_scanl:
  Deorbitalized SCAN (SCAN-L) exchange
  
• mgga_x_revscanl:
  Deorbitalized revised SCAN (revSCAN-L) exchange
  
• mgga_c_scanl:
  Deorbitalized SCAN (SCAN-L) correlation
  
• mgga_c_scanl_rvv10:
  SCAN-L + rVV10 correlation
  
• mgga_c_scanl_vv10:
  SCAN-L + VV10 correlation
  
• hyb_mgga_x_js18:
  Jana and Samal 2018, screened range-separated TM exchange
  
• hyb_mgga_x_pjs18:
  Patra, Jana and Samal 2018, screened range-separated TM exchange
  
• mgga_x_task:
  TASK exchange of Aschebrock and Kuemmel
  
• mgga_x_mggac:
  MGGAC exchange of Patra et al
  
• gga_c_mggac:
  beta fitted to LC20 to be used with MGGAC
  
• mgga_x_mbr:
  modified Becke-Roussel by Patra et al
  
• mgga_x_r2scanl:
  Deorbitalized re-regularized SCAN (r2SCAN-L) exchange
  
• mgga_c_r2scanl:
  Deorbitalized re-regularized SCAN (r2SCAN-L) correlation
  
• hyb_mgga_xc_lc_tmlyp:
  Long-range corrected TM-LYP by Jana et al
  
• mgga_x_mtask:
  modified TASK exchange
  
• gga_x_q1d:
  Functional for quasi-1D systems
  
• mgga_x_ktbm_0:
  KTBM learned exchange - 0
  
• mgga_x_ktbm_1:
  KTBM learned exchange - 1
  
• mgga_x_ktbm_2:
  KTBM learned exchange - 2
  
• mgga_x_ktbm_3:
  KTBM learned exchange - 3
  
• mgga_x_ktbm_4:
  KTBM learned exchange - 4
  
• mgga_x_ktbm_5:
  KTBM learned exchange - 5
  
• mgga_x_ktbm_6:
  KTBM learned exchange - 6
  
• mgga_x_ktbm_7:
  KTBM learned exchange - 7
  
• mgga_x_ktbm_8:
  KTBM learned exchange - 8
  
• mgga_x_ktbm_9:
  KTBM learned exchange - 9
  
• mgga_x_ktbm_10:
  KTBM learned exchange - 10
  
• mgga_x_ktbm_11:
  KTBM learned exchange - 11
  
• mgga_x_ktbm_12:
  KTBM learned exchange - 12
  
• mgga_x_ktbm_13:
  KTBM learned exchange - 13
  
• mgga_x_ktbm_14:
  KTBM learned exchange - 14
  
• mgga_x_ktbm_15:
  KTBM learned exchange - 15
  
• mgga_x_ktbm_16:
  KTBM learned exchange - 16
  
• mgga_x_ktbm_17:
  KTBM learned exchange - 17
  
• mgga_x_ktbm_18:
  KTBM learned exchange - 18
  
• mgga_x_ktbm_19:
  KTBM learned exchange - 19
  
• mgga_x_ktbm_20:
  KTBM learned exchange - 20
  
• mgga_x_ktbm_21:
  KTBM learned exchange - 21
  
• mgga_x_ktbm_22:
  KTBM learned exchange - 22
  
• mgga_x_ktbm_23:
  KTBM learned exchange - 23
  
• mgga_x_ktbm_24:
  KTBM learned exchange - 24
  
• mgga_x_ktbm_gap:
  KTBM learned exchange - GAP
  
• oep_x:
  OEP: Exact exchange (not from libxc).
  
• slater_x:
  Slater approximation to the exact exchange (not from libxc).
  
• fbe_x:
  Exchange functional based on the force balance equation (not from libxc).
  
• ks_inversion:
  Inversion of KS potential (not from libxc).
  
• rdmft_xc_m:
  RDMFT Mueller functional (not from libxc).
  
• xc_half_hartree:
  Half-Hartree exchange for two electrons (supports complex scaling) (not from libxc). Defined by $v_{xc}(r) = v_H(r) / 2$.
  
• hyb_gga_xc_mvorb_hse06:
  Density-based mixing parameter of HSE06 (not from libxc).
  
• hyb_gga_xc_mvorb_pbeh:
  Density-based mixing parameter of PBEH (not from libxc). At the moment this is not supported for libxc >= 4.0.
  
• vdw_c_vdwdf:
  van der Waals density functional vdW-DF correlation from libvdwxc (not from libxc). Use with gga_x_pbe_r.
  
• vdw_c_vdwdf2:
  van der Waals density functional vdW-DF2 correlation from libvdwxc (not from libxc). Use with gga_x_rpw86.
  
• vdw_c_vdwdfcx:
  van der Waals density functional vdW-DF-cx correlation from libvdwxc (not from libxc). Use with gga_x_lv_rpw86.
  
• none:
  Exchange and correlation set to zero (not from libxc).
  

Name XCKernel
Section Hamiltonian::XC
Type integer

Defines the exchange-correlation kernel. Only LDA kernels are available currently. The options are the same as XCFunctional. Note: the kernel is only needed for Casida, Sternheimer, or optimal-control calculations. Defaults:
1D: lda_x_1d + lda_c_1d_csc
2D: lda_x_2d + lda_c_2d_amgb
3D: lda_x + lda_c_pz_mod

Options:

• xc_functional:
  The same functional defined by XCFunctional.
  

Name XCKernelLRCAlpha
Section Hamiltonian::XC
Type float
Default 0.0

Set to a non-zero value to add a long-range correction for solids to the kernel. This is the $\alpha$ parameter defined in S. Botti et al., Phys. Rev. B 69, 155112 (2004). The $\Gamma = \Gamma = 0$ term $-\alpha/q^2$ is taken into account by introducing an additional pole to the polarizability (see R. Stubner <i>et al.</i>, <i>Phys. Rev. B</i> 70, 245119 (2004)). The rest of the terms are included by multiplying the Hartree term by $1 - \alpha / 4 \pi$. The use of non-zero $\alpha$ in combination with <tt>HamiltonianVariation</tt> = <tt>V_ext_only</tt> corresponds to account of only the $\Gamma = \Gamma = 0$ term. Applicable only to isotropic systems. (Experimental)

Name XCPhotonFunctional
Section Hamiltonian::XC
Type integer
Default 0

Defines the exchange and correlation functionals to be used for the QEDFT description of the electron-photon system.

Options:

• none:
  No functional is used
  
• photon_x_lda:
  Exchange-only local density approcimation
  
• photon_xc_lda:
  Exchange-correlation local density approcimation
  
• photon_x_wfn:
  Exchange-only based on wave functions
  
• photon_xc_wfn:
  Exchange-correlation based on wave functions
  

Name XCPhotonIncludeHartree
Section Hamiltonian::XC
Type logical
Default yes

Use the Hartree potential and energy in calculations

Name XCUseGaugeIndependentKED
Section Hamiltonian::XC
Type logical
Default yes

If true, when evaluating the XC functional, a term including the (paramagnetic or total) current is added to the kinetic-energy density such as to make it gauge-independent. Applies only to meta-GGA (and hybrid meta-GGA) functionals.