Available PAW potentials: Difference between revisions

From VASP Wiki
VisualWikitext
No edit summary
(Major rewrite to split this gigantic page into how-to pages and overview pages. Basically we (Michael and Marie-Therese) created a whole category pseudopotentials based on the information.)
Tag: New redirect
 
(29 intermediate revisions by 4 users not shown)
Line 1: Line 1:
PAW potentials for all elements in the periodic table are available. With the exception of the 1st row elements, all PAW potentials were generated to work reliably and accurately at an energy cutoff of roughly 250 eV (the default energy cutoff is read as {{TAG|ENMAX}} in the [[POTCAR]] file).
#REDIRECT [[Available pseudopotentials]]
The distributed PAW potentials have been generated by G. Kresse following the recipes discussed in {{cite|kresse:prb:99}}, whereas the PAW method has been first suggested and used by Peter Blöchl {{cite|bloechl:prb:94b}}.
If you use any of the supplied PAW potentials you should include these two references.
 
Generally the PAW potentials are more accurate than ultra-soft pseudopotentials (US-PP). There are two reasons for this: first, the radial cutoffs (core radii) are smaller than the radii used for US pseudopotentials, and second the PAW potentials reconstruct the exact valence wavefunction with all nodes in the core region. Since the core radii of the PAW potentials are smaller, the required energy cutoffs and basis sets are also somewhat larger. If such a high precision is not required, the older US-PP can be used. In practice, however, the increase in the basis set size will be usually small, since the energy cutoffs have not changed appreciably for C, N and O, so that calculations for model structures that include any of these elements are not more expensive with PAW than with US-PP.
 
For some elements several PAW versions exist. The standard version has generally no extension. An extension _h implies that the potential is harder than the standard potential and hence requires a greater energy cutoff. The extension _s means that the potential is softer than the standard version. The extensions _pv and _sv imply that the <math>p</math> and <math>s</math> semi-core states are treated as valence states (i.e. for V_pv the <math>3p</math> states are treated as valence states, and for V_sv the <math>3s</math> and <math>3p</math> states are treated as valence states). PAW files with an extension _d, treat the <math>d</math> semi core states as valence states (for Ga_d the <math>3d</math> states are treated as valence states).
 
In the following we will present the available PAW potentials. All distributed potentials have been tested using standard DFT-"benchmark" runs (see the ''data_base'' file in the released tar files). We strongly recommend to use the potentials only in VASP.5.4 or higher.
 
Recommended potentials are always reported in bold face.
 
The corresponding distribution directory of the potential is created by adding underscores between the elemental name and the extensions "_", e.g Li sv becomes Li_sv. All reported potentials are for PBE calculations. The reported cutoffs might differ slightly for LDA potentials.
 
== Recommended potentials for DFT calculations ==
 
The following table lists the standard PAW potentials for VASP.
 
'''Important Note''': If dimers with short bonds are present in the compound (O<sub>2</sub>, CO, N<sub>2</sub>, F<sub>2</sub>, P<sub>2</sub>, S<sub>2</sub>, Cl<sub>2</sub>), we recommend to use the _h potentials. Specifically, C_h, O_h, N_h, F_h, P_h, S_h, Cl_h.
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV) ||valency
|-
|'''H''' ||'''250''' ||'''1'''
|-             
|H AE ||1000 ||1
|-             
|H h ||700 ||1
|-             
|H s ||200 ||1
|-             
|'''He''' ||'''479''' ||'''2'''
|-             
|Li ||140 ||1
|-             
|'''Li sv''' ||'''499''' ||'''3'''
|-             
|'''Be''' ||'''248''' ||'''2'''
|-             
|Be sv ||309 ||4
|-             
|'''B''' ||'''319''' ||'''3'''
|-             
|B h ||700 ||3
|-             
|B s ||269 ||3
|-             
|'''C''' ||'''400''' ||'''4'''
|-             
|C h ||700 ||4
|-             
|C s ||274 ||4
|-             
|'''N''' ||'''400''' ||'''5'''
|-             
|N h ||700 ||5
|-             
|N s ||280 ||5
|-             
|'''O''' ||'''400''' ||'''6'''
|-             
|O h ||700 ||6
|-             
|O s ||283 ||6
|-             
|'''F''' ||'''400''' ||'''7'''
|-             
|F h ||700 ||7
|-             
|F s ||290 ||7
|-             
|'''Ne''' ||'''344''' ||'''8'''
|-             
|Na ||102 ||1
|-             
|'''Na pv''' ||'''260''' ||'''7'''
|-             
|Na sv ||646 ||9
|-             
|'''Mg''' ||'''200''' ||'''2'''
|-             
|Mg pv ||404 ||8
|-             
|Mg sv ||495 ||10
|-             
|'''Al''' ||'''240''' ||'''3'''
|-             
|'''Si''' ||'''245''' ||'''4'''
|-             
|'''P''' ||'''255''' ||'''5'''
|-             
|P h ||390 ||5
|-             
|'''S''' ||'''259''' ||'''6'''
|-             
|S h ||402 ||6
|-             
|'''Cl''' ||'''262''' ||'''7'''
|-             
|Cl h ||409 ||7
|-             
|'''Ar''' ||'''266''' ||'''8'''
|-             
|K pv ||117 ||7
|-             
|'''K sv''' ||'''259''' ||'''9'''
|-             
|Ca pv ||120 ||8
|-             
|'''Ca sv''' ||'''267''' ||'''10'''
|-             
|Sc ||155 ||3
|-             
|'''Sc sv''' ||'''223''' ||'''11'''
|-             
|Ti ||178 ||4
|-             
|Ti pv ||222 ||10
|-             
|'''Ti sv''' ||'''275''' ||'''12'''
|-             
|V ||193 ||5
|-             
|V pv ||264 ||11
|-             
|'''V sv''' ||'''264''' ||'''13'''
|-             
|Cr ||227 ||6
|-             
|'''Cr pv''' ||'''266''' ||'''12'''
|-             
|Cr sv ||395 ||14
|-             
|Mn ||270 ||7
|-             
|'''Mn pv''' ||'''270''' ||'''13'''
|-             
|Mn sv ||387 ||15
|-             
|'''Fe''' ||'''268''' ||'''8'''
|-             
|Fe pv ||293 ||14
|-             
|Fe sv ||391 ||16
|-             
|'''Co''' ||'''268''' ||'''9'''
|-             
|Co pv ||271 ||15
|-             
|Co sv ||390 ||17
|-             
|'''Ni''' ||'''270''' ||'''10'''
|-             
|Ni pv ||368 ||16
|-             
|'''Cu''' ||'''295''' ||'''11'''
|-             
|Cu pv ||369 ||17
|-             
|'''Zn''' ||'''277''' ||'''12'''
|-             
|Ga ||135 ||3
|-             
|'''Ga d''' ||'''283''' ||'''13'''
|-             
|Ga h ||405 ||13
|-             
|Ge ||174 ||4
|-             
|'''Ge d''' ||'''310''' ||'''14'''
|-             
|Ge h ||410 ||14
|-             
|'''As''' ||'''209''' ||'''5'''
|-             
|As d ||289 ||15
|-             
|'''Se''' ||'''212''' ||'''6'''
|-             
|'''Br''' ||'''216''' ||'''7'''
|-             
|'''Kr''' ||'''185''' ||'''8'''
|-             
|Rb pv ||122 ||7
|-             
|'''Rb sv''' ||'''220''' ||'''9'''
|-             
|'''Sr sv''' ||'''229''' ||'''10'''
|-             
|'''Y sv''' ||'''203''' ||'''11'''
|-             
|'''Zr sv''' ||'''230''' ||'''12'''
|-             
|Nb pv ||209 ||11
|-             
|'''Nb sv''' ||'''293''' ||'''13'''
|-             
|Mo ||225 ||6
|-             
|Mo pv ||225 ||12
|-             
|'''Mo sv''' ||'''243''' ||'''14'''
|-             
|Tc ||229 ||7
|-             
|'''Tc pv''' ||'''264''' ||'''13'''
|-             
|Tc sv ||319 ||15
|-             
|Ru ||213 ||8
|-             
|'''Ru pv''' ||'''240''' ||'''14'''
|-             
|Ru sv ||319 ||16
|-             
|Rh ||229 ||9
|-             
|'''Rh pv''' ||'''247''' ||'''15'''
|-             
|'''Pd''' ||'''251''' ||'''10'''
|-             
|Pd pv ||251 ||16
|-             
|'''Ag''' ||'''250''' ||'''11'''
|-             
|Ag pv ||298 ||17
|-             
|'''Cd''' ||'''274''' ||'''12'''
|-             
|In ||96 ||3
|-             
|'''In d''' ||'''239''' ||'''13'''
|-             
|Sn ||103 ||4
|-             
|'''Sn d''' ||'''241''' ||'''14'''
|-             
|'''Sb''' ||'''172''' ||'''5'''
|-             
|'''Te''' ||'''175''' ||'''6'''
|-             
|'''I''' ||'''176''' ||'''7'''
|-             
|'''Xe''' ||'''153''' ||'''8'''
|-             
|'''Cs sv''' ||'''220''' ||'''9'''
|-             
|'''Ba sv''' ||'''187''' ||'''10'''
|-             
|'''La''' ||'''219''' ||'''11'''
|-             
|La s ||137 ||9
|-             
|'''Ce''' ||'''273''' ||'''12'''
|-             
|Ce h ||300 ||12
|-             
|Ce 3 ||177 ||11
|-             
|Pr ||273 ||13
|-             
|'''Pr 3''' ||'''182''' ||'''11'''
|-             
|Nd ||253 ||14
|-             
|'''Nd 3''' ||'''183''' ||'''11'''
|-             
|Pm ||259 ||15
|-             
|'''Pm 3''' ||'''177''' ||'''11'''
|-             
|Sm ||258 ||16
|-             
|'''Sm 3''' ||'''177''' ||'''11'''
|-             
|Eu ||250 ||17
|-             
|'''Eu 2''' ||'''99''' ||'''8'''
|-             
|Eu 3 ||129 ||9
|-             
|Gd ||256 ||18
|-             
|'''Gd 3''' ||'''154''' ||'''9'''
|-             
|Tb ||265 ||19
|-             
|'''Tb 3''' ||'''156''' ||'''9'''
|-             
|Dy ||255 ||20
|-             
|'''Dy 3''' ||'''156''' ||'''9'''
|-             
|Ho ||257 ||21
|-             
|'''Ho 3''' ||'''154''' ||'''9'''
|-             
|Er 2 ||120 ||8
|-             
|'''Er 3''' ||'''155''' ||'''9'''
|-             
|Er ||298 ||22
|-             
|Tm ||257 ||23
|-             
|'''Tm 3''' ||'''149''' ||'''9'''
|-             
|Yb ||253 ||24
|-             
|'''Yb 2''' ||'''113''' ||'''8'''
|-             
|Lu ||256 ||25
|-             
|'''Lu 3''' ||'''155''' ||'''9'''
|-             
|Hf ||220 ||4
|-             
|'''Hf pv''' ||'''220''' ||'''10'''
|-             
|Hf sv ||237 ||12
|-             
|Ta ||224 ||5
|-             
|'''Ta pv''' ||'''224''' ||'''11'''
|-             
|W ||223 ||6
|-             
|'''W pv''' ||'''223''' ||'''12'''
|-             
|'''Re''' ||'''226''' ||'''7'''
|-             
|Re pv ||226 ||13
|-             
|'''Os''' ||'''228''' ||'''8'''
|-             
|Os pv ||228 ||14
|-             
|'''Ir''' ||'''211''' ||'''9'''
|-             
|'''Pt''' ||'''230''' ||'''10'''
|-             
|Pt pv ||295 ||16
|-             
|'''Au''' ||'''230''' ||'''11'''
|-             
|'''Hg''' ||'''233''' ||'''12'''
|-             
|Tl ||90 ||3
|-             
|'''Tl d''' ||'''237''' ||'''13'''
|-             
|Pb ||98 ||4
|-             
|'''Pb d''' ||'''238''' ||'''14'''
|-             
|Bi ||105 ||5
|-             
|'''Bi d''' ||'''243''' ||'''15'''
|-             
|Po ||160 ||6
|-             
|'''Po d''' ||'''265''' ||'''16'''
|-             
|At ||161 ||7
|-             
|'''At d''' ||'''266''' ||'''17'''
|-             
|'''Rn''' ||'''152''' ||'''8'''
|-             
|'''Fr sv''' ||'''215''' ||'''9'''
|-             
|'''Ra sv''' ||'''237''' ||'''10'''
|-             
|'''Ac''' ||'''172''' ||'''11'''
|-             
|'''Th''' ||'''247''' ||'''12'''
|-             
|Th s ||169 ||10
|-             
|'''Pa''' ||'''252''' ||'''13'''
|-             
|Pa s ||193 ||11
|-             
|'''U''' ||'''253''' ||'''14'''
|-             
|U s ||209 ||14
|-             
|'''Np''' ||'''254''' ||'''15'''
|-             
|Np s ||208 ||15
|-             
|'''Pu''' ||'''254''' ||'''16'''
|-             
|Pu s ||208 ||16
|-             
|'''Am''' ||'''256''' ||'''17'''
|-             
|'''Cm''' ||'''258''' ||'''18'''
|-
|}
 
Hydrogen like potentials are supplied for a valency between 0.25 and 1.75 as listed in the table below:
 
{| class="wikitable"
|-
|Element (and appendix)        ||default cutoff ENMAX (eV)    ||valency
|-
|H .25          ||250  ||0.2500
|-
|H .33          ||250  ||0.3300
|-
|H .42          ||250  ||0.4200
|-
|H .5          ||250  ||0.5000
|-
|H .58          ||250  ||0.5800
|-
|H .66          ||250  ||0.6600
|-
|H .75          ||250  ||0.7500
|-
|H 1.25        ||250  ||1.2500
|-
|H 1.33        ||250  ||1.3300
|-
|H 1.5          ||250  ||1.5000
|-
|H 1.66        ||250  ||1.6600
|-
|H 1.75        ||250  ||1.7500
|-
|}
 
== Recommended potentials for GW/RPA calculations ==
 
The available GW potentials are listed in the Table below. As documented in the ''data_base'' file released with the PAW potentials, for density functional calculations, the GW potentials yield virtually identical results as the standard potentials, and it is safe to assume that one can use the GW potentials instead of standard LDA/GGA potentials for groundstate calculations without deteriorating the results. In fact, we believe the GW potentials are generally at least as good as the DFT standard potentials, but might be much better for excited state properties.
 
In general, the GW potentials yield much better scattering properties at high energies well above the Fermi-level (typically up to 10-20 Ry above the vacuum level). This is believed to be important for GW and RPA calculations.
 
'''Important Note''': If dimers with short bonds are present in the compound (O<sub>2</sub>, CO, N<sub>2</sub>, F<sub>2</sub>, P<sub>2</sub>, S<sub>2</sub>, Cl<sub>2</sub>), we recommend to use the _h potentials. Specifically, C_GW_h, O_GW_h, N_GW_h, F_GW_h.
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV) ||valency
|-
|'''H GW''' ||'''300''' ||'''1'''
|-
|H h GW ||700 ||1
|-
|'''He GW''' ||'''405''' ||'''2'''
|-
|'''Li sv GW''' ||'''434''' ||'''3'''
|-
|Li GW ||112 ||1
|-
|Li AE GW ||434 ||3
|-
|'''Be sv GW''' ||'''537''' ||'''4'''
|-
|Be GW ||248 ||2
|-
|'''B GW''' ||'''319''' ||'''3'''
|-
|'''C GW''' ||'''414''' ||'''4'''
|-
|C GW new ||414 ||4
|-
|C h GW ||741 ||4
|-
|'''N GW''' ||'''421''' ||'''5'''
|-
|N GW new ||421 ||5
|-
|N h GW ||755 ||5
|-
|N s GW ||296 ||5
|-
|'''O GW''' ||'''415''' ||'''6'''
|-
|O GW new ||434 ||6
|-
|O h GW ||765 ||6
|-
|O s GW ||335 ||6
|-
|'''F GW''' ||'''488''' ||'''7'''
|-
|F GW new ||488 ||7
|-
|F h GW ||848 ||7
|-
|'''Ne GW''' ||'''432''' ||'''8'''
|-
|Ne s GW ||318 ||8
|-
|'''Na sv GW''' ||'''372''' ||'''9'''
|-
|'''Mg sv GW''' ||'''430''' ||'''10'''
|-
|Mg GW ||126 ||2
|-
|Mg pv GW ||404 ||8
|-
|'''Al GW''' ||'''240''' ||'''3'''
|-
|Al sv GW ||411 ||11
|-
|'''Si GW''' ||'''245''' ||'''4'''
|-
|Si GW new ||245 ||4
|-
|Si sv GW ||548 ||12
|-
|'''P GW''' ||'''255''' ||'''5'''
|-
|'''S GW''' ||'''259''' ||'''6'''
|-
|'''Cl GW''' ||'''262''' ||'''7'''
|-
|'''Ar GW''' ||'''290''' ||'''8'''
|-
|'''K sv GW''' ||'''249''' ||'''9'''
|-
|'''Ca sv GW''' ||'''281''' ||'''10'''
|-
|'''Sc sv GW''' ||'''378''' ||'''11'''
|-
|'''Ti sv GW''' ||'''383''' ||'''12'''
|-
|'''V sv GW''' ||'''382''' ||'''13'''
|-
|'''Cr sv GW''' ||'''384''' ||'''14'''
|-
|'''Mn sv GW''' ||'''384''' ||'''15'''
|-
|Mn GW ||278 ||7
|-
|'''Fe sv GW''' ||'''387''' ||'''16'''
|-
|Fe GW ||321 ||8
|-
|'''Co sv GW''' ||'''387''' ||'''17'''
|-
|Co GW ||323 ||9
|-
|'''Ni sv GW''' ||'''389''' ||'''18'''
|-
|Ni GW ||357 ||10
|-
|'''Cu sv GW''' ||'''467''' ||'''19'''
|-
|Cu GW ||417 ||11
|-
|'''Zn sv GW''' ||'''401''' ||'''20'''
|-
|Zn GW ||328 ||12
|-
|'''Ga d GW''' ||'''404''' ||'''13'''
|-
|Ga GW ||135 ||3
|-
|Ga sv GW ||404 ||21
|-
|'''Ge d GW''' ||'''375''' ||'''14'''
|-
|Ge sv GW ||410 ||22
|-
|Ge GW ||174 ||4
|-
|'''As GW''' ||'''209''' ||'''5'''
|-
|As sv GW ||415 ||23
|-
|'''Se GW''' ||'''212''' ||'''6'''
|-
|Se sv GW ||469 ||24
|-
|'''Br GW''' ||'''216''' ||'''7'''
|-
|Br sv GW ||475 ||25
|-
|'''Kr GW''' ||'''252''' ||'''8'''
|-
|'''Rb sv GW''' ||'''221''' ||'''9'''
|-
|'''Sr sv GW''' ||'''225''' ||'''10'''
|-
|'''Y sv GW''' ||'''339''' ||'''11'''
|-
|'''Zr sv GW''' ||'''346''' ||'''12'''
|-
|'''Nb sv GW''' ||'''353''' ||'''13'''
|-
|'''Mo sv GW''' ||'''344''' ||'''14'''
|-
|'''Tc sv GW''' ||'''351''' ||'''15'''
|-
|'''Ru sv GW''' ||'''348''' ||'''16'''
|-
|'''Rh sv GW''' ||'''351''' ||'''17'''
|-
|Rh GW ||247 ||9
|-
|'''Pd sv GW''' ||'''356''' ||'''18'''
|-
|Pd GW ||251 ||10
|-
|'''Ag sv GW''' ||'''354''' ||'''19'''
|-
|Ag GW ||250 ||11
|-
|'''Cd sv GW''' ||'''361''' ||'''20'''
|-
|Cd GW ||254 ||12
|-
|'''In d GW''' ||'''279''' ||'''13'''
|-
|In sv GW ||366 ||21
|-
|'''Sn d GW''' ||'''260''' ||'''14'''
|-
|Sn sv GW ||368 ||22
|-
|'''Sb d GW''' ||'''263''' ||'''15'''
|-
|Sb sv GW ||372 ||23
|-
|Sb GW ||172 ||5
|-
|'''Te GW''' ||'''175''' ||'''6'''
|-
|Te sv GW ||376 ||24
|-
|'''I GW''' ||'''176''' ||'''7'''
|-
|I sv GW ||381 ||25
|-
|'''Xe GW''' ||'''180''' ||'''8'''
|-
|Xe sv GW ||400 ||26
|-
|'''Cs sv GW''' ||'''198''' ||'''9'''
|-
|'''Ba sv GW''' ||'''238''' ||'''10'''
|-
|'''La GW''' ||'''313''' ||'''11'''
|-
|'''Ce GW''' ||'''305''' ||'''12'''
|-
|'''Hf sv GW''' ||'''283''' ||'''12'''
|-
|'''Ta sv GW''' ||'''286''' ||'''13'''
|-
|'''W sv GW''' ||'''317''' ||'''14'''
|-
|'''Re sv GW''' ||'''317''' ||'''15'''
|-
|'''Os sv GW''' ||'''320''' ||'''16'''
|-
|'''Ir sv GW''' ||'''320''' ||'''17'''
|-
|'''Pt sv GW''' ||'''324''' ||'''18'''
|-
|Pt GW ||249 ||10
|-
|'''Au sv GW''' ||'''306''' ||'''19'''
|-
|Au GW ||248 ||11
|-
|'''Hg sv GW''' ||'''312''' ||'''20'''
|-
|'''Tl d GW''' ||'''237''' ||'''15'''
|-
|Tl sv GW ||316 ||21
|-
|'''Pb d GW''' ||'''238''' ||'''16'''
|-
|Pb sv GW ||317 ||22
|-
|'''Bi d GW''' ||'''261''' ||'''17'''
|-
|Bi GW ||147 ||5
|-
|Bi sv GW ||323 ||23
|-
|'''Po d GW''' ||'''267''' ||'''18'''
|-
|Po sv GW ||326 ||24
|-
|'''At d GW''' ||'''266''' ||'''17'''
|-
|At sv GW ||328 ||25
|-
|'''Rn d GW''' ||'''268''' ||'''18'''
|-
|Rn sv GW ||331 ||26
|-
|}
 
== Further recommendations for the potentials ==
 
In the following we further explanation the potentials for very important element groups.
 
=== 1st row elements ===
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV)
|-
|'''B''' ||'''318''' ||'''3'''
|-
|B_h ||700 ||3
|-
|B_s ||250  ||3
|-
|'''C''' ||'''400'''    ||'''4'''
|-
|C_h ||700 ||4
|-
|C_s ||273  ||4
|-
|'''N''' ||'''400'''    ||'''5'''
|-
|N_h ||700              ||5
|-
|N_s ||250           ||5
|-
|'''O''' ||'''400'''  ||'''6'''
|-
|O_h ||700 ||6
|-
|O_s ||250  ||6
|-
|'''F''' ||'''400'''    ||'''7'''
|-
|F_h ||700   ||7
|-
|F_s ||250   ||7
|-
|Ne ||343    ||8
|-
|}
 
For the 1st row elements three PAW versions exist. For most purposes the standard versions should be used. They yield reliable results for cutoffs between 325 and 400 eV, where 370-400 eV are required to accurately predict vibrational properties, but binding geometries and energy differences are well reproduced at 325 eV. The typical bond length errors for first row dimers (N<sub>2</sub>, CO, O<sub>2</sub>) are about 1% (compared to more accurate DFT calculations, not experiment). The hard pseudopotentials _h give results that are essentially identical to the best DFT calculations presently available (FLAPW, or Gaussian with huge basis sets). The soft potentials are optimised to work around 250-280 eV. They yield very reliable description for most oxides, such as V<sub>x</sub>O<sub>y</sub>, TiO<sub>2</sub>, CeO<sub>2</sub>, but fail to describe some structural details in zeolites (i.e. cell parameters, and volume).
 
For HF and hybrid tpye calculations, we strictly recommend the use of the standard, standard GW, or of the hard potentials. For instance, the O_s potential can cause unacceptably large error even in transition metal oxides, even though the potential works reliable at the PBE level.
 
=== Alkali and alkali-earth elements (simple metals) ===
 
For Li (and Be), a standard potential and a potential that treats the 1s shell as valence states are available (Li_sv, Be_sv). For many applications one should use the _sv potential since their transferability is much improved compared to the standard potentials.
 
For the other alkali and alkali-earth elements the semi-core s and p states should be treated as valence states as well. For lighter elements (Na-Ca) it is usually sufficient to treat the the 2p and 3p states, respectively, as valence states (_pv), whereas for Rb-Sr the 4s, 4p and  5s, 5p states, respectively, must be treated as valence states (_sv). The standard potentials are listed below (default energy cutoffs are specified as well but might vary from one release to the other):
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV) ||valency
|-
|'''H''' ||'''250''' ||'''1'''
|- 
|H_h ||700 ||1
|-
|Li ||140 ||1
|-
|'''Li_sv''' ||'''500''' ||'''3'''
|-
|Na ||100 ||1
|-
|'''Na_pv''' ||'''260''' ||'''7'''
|-
|Na_sv ||700 ||9
|- 
|K_pv ||120 ||7
|-
|'''K_sv''' ||'''260''' ||'''9'''
|-
|Rb_pv ||120 ||7
|- 
|'''Rb_sv''' ||'''220''' ||'''9'''
|-
|'''Cs_sv''' ||'''220'''  ||'''9'''
|-
|'''Be''' ||'''300'''  ||'''2'''
|-
|Be_sv ||308  ||4
|-
|'''Mg''' ||'''210'''  ||'''2'''
|-
|Mg_pv ||400  ||8
|-
|Mg_sv  ||495  ||10
|-
|Ca_pv ||120  ||8
|-
|'''Ca_sv''' ||'''270'''  ||'''10'''
|-
|'''Sr_sv''' ||'''230'''  ||'''10'''
|-
|'''Ba_sv''' ||'''190'''  ||'''10'''
|-
|}
 
 
Contrary to the common believe, these elements are exceedingly difficult to pseudize in particular in combination with strongly electronegative elements (F) errors can be larger then usual. The present potentials are very precise, and should offer a very reliable description. For X_pv potentials the semicore p states are treated as valence (2p in Na and Mg, 3p in K and Ca etc.). For X_sv potentials, the semicore s states are treated as valence (1s in Li and Be, 2s in Na etc.)
 
=== d-elements ===
The same applies to d-elements as for the alkali and earth-alkali metals: the semi-core p states and possibly the semi-core s states should be treated as valence states. In most cases, however, reliable results can be obtained even if the semi core states are kept frozen. As a rule of thumb the p states should be treated as valence states, if their eigenenergy <math>\epsilon</math> lies above 3 Ry.
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV) ||valency
|-
|Sc ||154 ||3
|-
|'''Sc_sv''' ||'''222''' ||'''11'''
|-
|'''Fe''' ||'''267''' ||'''8'''
|-
|Fe_pv ||293 ||14
|-
|Fe_sv ||390 ||16            
|-
|'''Y_sv''' ||'''203''' ||'''11'''
|-
|Ru ||213 ||8
|-
|'''Ru_pv''' ||'''240''' ||'''14'''
|-
|Ru_sv  ||319    ||16      
|-
|'''Os''' ||'''228''' ||'''8'''
|-
|Os_pv ||228 ||14        
|-
|Ti ||178    ||4
|-
|Ti_pv ||222    ||10
|-
|'''Ti_sv''' ||'''274'''    ||'''12'''
|-
|'''Co''' ||'''267'''    ||'''9'''
|-
|Co_pv ||271    ||15
|-
|Co_sv ||390    ||17
|-
|'''Zr_sv''' ||'''229'''    ||'''12'''
|-
|Rh ||228    ||9
|-
|'''Rh_pv''' ||'''250'''    ||'''15'''
|-
|Hf ||220    ||4
|-
|'''Hf_pv''' ||'''220'''    ||'''10'''
|-
|'''Ir''' ||'''210'''    ||'''9'''
|-
|V ||192    ||5
|-
|V_pv ||263 ||11     
|-
|'''V_sv''' ||'''263'''    ||'''13'''
|-
|'''Ni''' ||'''269'''    ||'''10'''
|-
|Ni_pv ||367    ||16
|-
|Nb_pv ||207 ||11     
|-
|'''Nb_sv''' ||'''293'''    ||'''13'''
|-
|'''Pd''' ||'''250'''    ||'''10'''
|-
|Pd_pv ||250    ||16
|-
|Ta ||223    ||5
|-
|'''Ta_pv''' ||'''223'''    ||'''11'''
|-
|'''Pt''' ||'''230'''    ||'''10'''
|-
|Pt_pv ||294    ||16
|-
|Cr ||227    ||6
|-
|'''Cr_pv''' ||'''265'''    ||'''12'''
|-
|Cr_sv ||395    ||14
|-
|'''Cu''' ||'''290'''    ||'''11'''
|-
|Cu_pv ||368    ||17
|-
|Mo ||224 ||6     
|-
|Mo_pv ||224    ||12
|-
|'''Mo_sv''' ||'''242'''    ||'''14'''
|-
|'''Ag''' ||'''249'''    ||'''11'''
|-
|Ag_pv  ||298    ||17
|-
|W ||223    ||6
|-
|'''W_pv''' ||'''223'''    ||'''12'''
|-
|'''Au''' ||'''229'''    ||'''11'''
|-
|Mn ||269    ||7
|-
|'''Mn_pv''' ||'''269'''    ||'''13'''
|-
|Mn_sv ||387    ||15
|-
|'''Zn''' ||'''276'''    ||'''12'''
|-
|Tc ||228    ||7
|-
|'''Tc_pv''' ||'''263'''    ||'''13'''
|-
|Tc_sv ||318    ||15
|-
|'''Cd''' ||'''274'''    ||'''12'''
|-
|'''Re''' ||'''226'''    ||'''7'''
|-
|Re_pv ||226    ||13
|-
|'''Hg''' ||'''233'''    ||'''12'''
|-
|}
 
 
For X_pv potentials, the semi core p states are treated as valence, whereas for X_sv pseudopotentials, the semi core s states are treated as valence. X_pv potentials are required for early transition metals, but one can freeze the semi-core p states for late transition metals (in particular noble metals).
 
When to switch from X_pv potentials to the X potentials depends on the required accuracy and the row for the 3d elements, even the Ti, V and Cr potentials give reasonable results, but should be used with uttermost care. 4d elements are most problematic, and I advice to use the X_pv potentials up to Tc_pv. For 5d elements the 5p states are rather strongly localized (below 3 Ry), since the 4f shell becomes filled. One can use the standard potentials starting from Hf, but we recommend to perform test calculations. For some elements, X_sv potential are available (e.g. Nb_sv, Mo_sv, Hf_sv). These potential usually have very similar cutoffs as the _pv potentials, and can be used as well. For HF type and hybrid functional calculations, we strongly recommend the use of the _sv and _pv potentials whenever possible.
 
=== p-elements including first row ===
 
{| class="wikitable"
|-
|Element (and appendix) ||default cutoff ENMAX (eV) ||valency
|-
|B_h ||700 ||3  
|-
|'''B''' ||'''318''' ||'''3'''
|-
|B_s ||250 ||3
|-
|'''Al''' ||'''240''' ||'''3'''
|-
|Ga ||134 ||3
|-
|'''Ga_d''' ||'''282''' ||'''13'''             
|-
|Ga_h ||404 ||13             
|-
|In ||95 ||3
|-
|'''In_d''' ||'''239''' ||'''13'''             
|-
|Tl ||90 ||3
|-
|'''Tl_d''' ||'''237''' ||'''13'''  
|-
|C_h ||700          ||4
|-
|'''C''' ||'''400'''          ||'''4'''
|-
|C_s ||273          ||4
|-
|'''Si''' ||'''245'''          ||'''4'''
|-
|Ge ||173          ||4
|-
|'''Ge_d''' ||'''310'''          ||'''14'''
|-
|Ge_h ||410          ||14
|-
|Sn ||103          ||4
|-
|'''Sn_d''' ||'''241'''          ||'''14'''
|-
|Pb ||97            ||4
|-
|'''Pb_d''' ||'''237'''          ||'''14'''
|-
|N_h ||700          ||5
|-
|'''N''' ||'''400'''          ||'''5'''
|-
|N_s ||250          ||5
|-
|'''P''' ||'''260'''          ||'''5'''
|-
|P_h ||390          ||5
|-
|'''As''' ||'''208'''          ||'''5'''
|-
|As d ||289          ||15
|-
|'''Sb''' ||'''172'''          ||'''5'''
|-
|Bi ||105          ||5
|-
|'''Bi_d''' ||'''242'''          ||'''15'''
|-
|O_h ||700          ||6
|-
|'''O''' ||'''400'''          ||'''6'''
|-
|O_s ||250          ||6
|-
|'''S''' ||'''260'''          ||'''6'''
|-
|S_h ||402          ||6
|-
|'''Se''' ||'''211'''          ||'''6'''
|-
|'''Te''' ||'''174'''          ||'''6'''
|-
|Po ||159          ||6
|-
|'''Po_d''' ||'''264'''          ||'''16'''
|-
|F_h ||700          ||7
|-
|'''F''' ||'''400'''          ||'''7'''
|-
|F_s ||250          ||7
|-
|'''Cl''' ||'''260'''          ||'''7'''
|-
|Cl_h ||409          ||7
|-
|'''Br''' ||'''216'''          ||'''7'''
|-
|'''I''' ||'''175'''          ||'''7'''
|-
|At ||161          ||7
|-
|'''At_d''' ||'''266'''          ||'''17'''
|-
|Ne ||343          ||8
|-
|Ar ||266          ||8
|-
|Kr ||185          ||8
|-
|Xe ||153          ||8
|-
|Rn ||152          ||8
|-
|}
 
For Ga, Ge, In, Sn, Tl-At the lower lying d states should treated as valence states (_d potential). For these elements, alternative potentials that treat the d states as core states are available as well, but should be used with great care.
 
=== f-elements ===
Due to self-interaction errors, f-electrons are not handled well by presently available density functionals. In particular, partially filled f states are often incorrectly described, leading to large errors for Pr-Eu and Tb-Yb where the error increases in the middle (Gd is handled reasonably well, since 7 electrons occupy the majority f shell). These errors are DFT and not VASP related. Particularly problematic is the description of the transition from an itinerant (band-like) behavior observed at the beginning of each period to localized states towards the end of the period. For the 4f elements, this transition occurs already in La and Ce, whereas the transition sets in for Pu and Am for the 5f elements. A routine way to cope with the inabilities of present DFT functionals to describe the localized 4f electrons is to place the 4f electrons in the core. Such potentials are available and described below. Furthermore, PAW potentials in which the f states are treated as valence states are available, but these potentials are not expected to work reliable when the f electrons are localized. Expertise using hybrid functionals or an LDA+U like treatment are not particularly large, but hybrid functionals should improve the description, if the f electrons are localized, although the most likely fail of the f electrons for band-like (itinerant) states.
 
== References ==
<references/>
 
<noinclude>
----
[[Category:PAW]][[Category:Howto]]

Latest revision as of 15:38, 11 June 2024

Redirect to:

Retrieved from "https://www.vasp.at/wiki/index.php?title=Available_PAW_potentials&oldid=24990"