LIBXC1: Difference between revisions

Revision as of 10:10, 28 December 2021

LIBXC1 = [integer] or [string]

Description: LIBXC1 and LIBXC2 specify the functionals from the library of exchange-correlation functionals Libxc ^[1]^[2] that one wants to use.

LIBXC1 and LIBXC2 can be either integers or strings. The available functionals are listed on the Libxc website^[3] along with their associated tag and number (e.g., GGA_X_PBE and 101 for PBE exchange). The tag indicates if this is an exchange (X), correlation (C) or exchange-correlation (XC) functional, and to which family it belongs to, namely LDA (LDA or HYB_LDA), GGA (GGA or HYB_GGA) or meta-GGA (MGGA or HYB_MGGA).

The possibilities for LIBXC1 and LIBXC2 are the following:

Both LIBXC1 and LIBXC2 are specified and correspond to the exchange and correlation functionals, respectively, or the reverse.
Only LIBXC1 (or LIBXC2) is specified and corresponds to an exchange or exchange-correlation functional. It can also be a correlation functional, but such a calculation without exchange would not make sense.

One has to specify also GGA = LIBXC for LDA, GGA and GGA-based hybrid functionals or METAGGA = LIBXC for meta-GGA functionals (hybrid-based meta-GGA functionals are not yet available in VASP).

Examples of how to specify a Libxc functional in INCAR are given below for the PBE^[4], SCAN^[5] and PBEh (PBE0)^[6] functionals.

PBE

GGA = LIBXC
LIBXC1 = 101
LIBXC2 = 130

or

GGA = LIBXC
LIBXC1 = GGA_X_PBE
LIBXC2 = GGA_C_PBE

SCAN

METAGGA = LIBXC
LIBXC1 = 263
LIBXC2 = 267

or

METAGGA = LIBXC
LIBXC1 = MGGA_X_SCAN
LIBXC2 = MGGA_C_SCAN

PBEh (PBE0)

LHFCALC = .TRUE.
AEXX = 0.25
GGA = LIBXC
LIBXC1 = 406

or

LHFCALC = .TRUE.
AEXX = 0.25
GGA = LIBXC
LIBXC1 = HYB_GGA_XC_PBEH

Related Tags and Sections

AGGAX, AGGAC, ALDAC, LHFCALC, hybrid functionals, settings for specific hybrid functionals

Examples that use this tag

[marques:cpc:2012-1] M. A. L. Marques, M. J. T. Oliveira, and T. Burnus, Comput. Phys. Commun., 183, 2272 (2012).

[lehtola:sx:2018-2] S. Lehtola, C. Steigemann, M. J. T. Oliveira, and M. A. L. Marques, SoftwareX, 7, 1 (2018).

[libxc-3] ttps://www.tddft.org/programs/libxc/]

[perdew:prl:1996-4] J. P. Perdew, K. Burke, and M. Ernzerhof, Phys. Rev. Lett., 77, 3865 (1996).

[sun:prl:15-5] J. Sun, A. Ruzsinszky, and J. P. Perdew, Phys. Rev. Lett. 115, 036402 (2015).

[adamo:jcp:1999-6] C. Adamo and V. Barone, Phys. Rev. Lett., 110, 6158 (1999).

[1]

[2]

[3]

[4]

[5]

[6]

@@ Line 1: / Line 1: @@
-{{TAGDEF|LIBXC1|}} [integer] or [string]}}
+{{TAGDEF|LIBXC1|[integer] or [string]}}
-Description: {{TAG|LIBXC1}} and {{TAG|LIBXC2|LIBXC2}} specify the functionals from the library of exchange-correlation functionals {{cite|marques:cpc:2012}}{{cite|lehtola:sx:2018}} that one wants to use.
+Description: {{TAG|LIBXC1}} and [[LIBXC1|LIBXC2]] specify the functionals from the library of exchange-correlation functionals Libxc {{cite|marques:cpc:2012}}{{cite|lehtola:sx:2018}} that one wants to use.
 ----
-{{TAG|LIBXC1}} and [[LIBXC1|LIBXC2]] can be either integers or strings. The available functionals are listed on the Libxc website<ref name="libxc"/> and are essentially of three types: exchange (_X_), correlation (_C_) or exchange-correlation (_XC_). The possibilities for {{TAG|LIBXC1}} and {{TAG|LIBXC2}} are the following:
+{{TAG|LIBXC1}} and [[LIBXC1|LIBXC2]] can be either integers or strings. The available functionals are listed on the Libxc website<ref name="libxc"/> along with their associated tag and number (e.g., GGA_X_PBE and 101 for PBE exchange). The tag indicates if this is an exchange (X), correlation (C) or exchange-correlation (XC) functional, and to which family it belongs to, namely LDA (LDA or HYB_LDA), GGA (GGA or HYB_GGA) or meta-GGA (MGGA or HYB_MGGA).
-*Both {{TAGDEF|LIBXC1}} and {{TAGDEF|LIBXC2}} are specified and correspond to the exchange (_X_) and correlation (_C_) functionals, respectively, or the reverse.
+The possibilities for {{TAG|LIBXC1}} and [[LIBXC1|LIBXC2]] are the following:
-*Only {{TAGDEF|LIBXC1}} (or {{TAGDEF|LIBXC2}}) is specified and corresponds to an exchange (_X_) or exchange-correlation (_XC_) functional. It can also be a correlation (_C_) functional, but such a calculation without exchange would not make sense. Examples of how to specify a Libxc functional in {{FILE|INCAR}} are given below for the PBE{{cite|perdew:prl:1996}} and SCAN functionals{{cite|sun:prl:15}}.
+*Both {{TAGDEF|LIBXC1}} and [[LIBXC1|LIBXC2]] are specified and correspond to the exchange and correlation functionals, respectively, or the reverse.
+*Only {{TAGDEF|LIBXC1}} (or [[LIBXC1|LIBXC2]]) is specified and corresponds to an exchange or exchange-correlation functional. It can also be a correlation functional, but such a calculation without exchange would not make sense.
+One has to specify also {{TAG|GGA}} = LIBXC for LDA, GGA and GGA-based hybrid functionals or {{TAG|METAGGA}} = LIBXC for meta-GGA functionals (hybrid-based meta-GGA functionals are not yet available in VASP).
+Examples of how to specify a Libxc functional in {{FILE|INCAR}} are given below for the PBE{{cite|perdew:prl:1996}}, SCAN{{cite|sun:prl:15}} and PBEh (PBE0){{cite|adamo:jcp:1999}} functionals.
 *PBE
   {{TAG|GGA}} = LIBXC
   {{TAG|LIBXC1}} = 101
-  {{TAG|LIBXC2}} = 130
+  [[LIBXC1|LIBXC2]] = 130
 or
   {{TAG|GGA}} = LIBXC
   {{TAG|LIBXC1}} = GGA_X_PBE
-  {{TAG|LIBXC2}} = GGA_C_PBE
+  [[LIBXC1|LIBXC2]] = GGA_C_PBE
 *SCAN
   {{TAG|METAGGA}} = LIBXC
   {{TAG|LIBXC1}} = 263
-  {{TAG|LIBXC2}} = 267
+  [[LIBXC1|LIBXC2]] = 267
 or
   {{TAG|METAGGA}} = LIBXC
   {{TAG|LIBXC1}} = MGGA_X_SCAN
-  {{TAG|LIBXC2}} = MGGA_C_SCAN
+ [[LIBXC1|LIBXC2]] = MGGA_C_SCAN
+*PBEh (PBE0)
+ {{TAG|LHFCALC}} = .TRUE.
+ {{TAG|AEXX}} = 0.25
+ {{TAG|GGA}} = LIBXC
+  {{TAG|LIBXC1}} = 406
+or
+ {{TAG|LHFCALC}} = .TRUE.
+ {{TAG|AEXX}} = 0.25
+ {{TAG|GGA}} = LIBXC
+ {{TAG|LIBXC1}} = HYB_GGA_XC_PBEH
 <references>