Available PAW potentials

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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 ENMAX in the POTCAR file). The distributed PAW potentials have been generated by G. Kresse following the recipes discussed in [1], whereas the PAW method has been first suggested and used by Peter Blöchl [2]. 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 and semi-core states are treated as valence states (i.e. for V_pv the states are treated as valence states, and for V_sv the and states are treated as valence states). PAW files with an extension _d, treat the semi core states as valence states (for Ga_d the 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 POTCAR files version 5.4 that are available on the download portal. The currently distributed POTCAR files version 5.4 posses a unique SHA hash. The POTCAR files version 5.2 are also quite popular and have been used in the Materials Project. They can be also downloaded from the VASP portal. Differences between version 5.4 and 5.2 are usually small, and limited to the few elements/POTCAR files. These differences will be documented here at a later point. Each POTCAR file of version 5.2 that is presently available on the VASP portal also posses a unique SHA hash, and they have been slightly edited in the headers (text part, which is not relevant to vasp calculations). If strict compatibility is required to the versions previously available at the univie server, one can also download the versions "VASP release PAW POTCAR files: LDA & PBE, 5.2 & 5.4 (original univie release version)".

Below, recommended potentials are always reported in bold face.

All reported potentials are for PBE calculations. The reported cutoffs might differ slightly for LDA potentials, as well as for different releases (please inspect the recommended cutoffs in the release POTCAR files).

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 (O2, CO, N2, F2, P2, S2, Cl2), we recommend to use the _h potentials. Specifically, C_h, O_h, N_h, F_h, P_h, S_h, Cl_h. Note that the listed default cutoffs might slightly change between different releases as noted above.

The potential W_pv available in older releases has been replaced by W_sv in version 5.4, and the At_d POTCAR file is no longer available, because the potential lead to fairly large errors in the lattice constants.

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 773 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_sv 223 14
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
Rn 151 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. Note that further potentials might become available, and the list is not always up to date. Another issue noteworthy mentioning is that the POTCAR files a restriction on the number of digits for the valency (typically 2, at most 3 digits). This means that using three H.33 potentials does not yield 0.99 electrons and not 1.00 electrons. This can cause hole or electron like states that are undesirable. The solution is to slightly adjusted NELECT in the INCAR file.

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 theory calculations, the GW potentials yield virtually identical results as the standard potentials, and one can use the GW potentials instead of standard LDA/GGA potentials for Kohn Sham calculations without deteriorating the results. In fact, we have evidence from comparison with all-electron calculations that the GW potentials are slightly superior even for DFT calculations. They are certainly superior for excited state properties, GW calculations, RPA calculations, and in general for any explicitly correlated wave function calculation (MP2, coupled cluster).

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).

Important Note: If dimers with short bonds are present in the compound (O2, CO, N2, F2, P2, S2, Cl2), we recommend to use the _h potentials. Specifically, C_GW_h, O_GW_h, N_GW_h, F_GW_h.

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 313 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 309 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

The C_GW_new, N_GW_new, O_GW_new and F_GW_new POTCAR files, use the f-pseudpotential as local potential, and posses d-projectors, whereas the C_GW, N_GW, O_GW and F_GW POTCAR files use the d-pseudpotential as local potential and posses no d-projectors. Calculations converge usually faster with respect to the energy cutoff ENMAX using the C_GW, N_GW, O_GW and G_GW potentials. Whether the new potentials posses a precision advantage over the old potentials is not entirely clear (in theory they should be more precise for correlated wave function calculations, however in practice the improvements seem to be modest and often do not justify the greater computational load).

Further recommendations for the potentials

In the following we further explanation the potentials for very important element groups.

1st row elements

Element (and appendix) default cutoff ENMAX (eV)
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 773 7
F_s 290 7
Ne 344 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 already well reproduced at 325 eV. The typical bond length errors for first row dimers (N2, CO, O2) are about 1% (compared to more accurate DFT calculations). The hard pseudopotentials _h give results that are essentially identical to the best DFT calculations presently available (FLAPW, or Gaussian with very large basis sets). The soft potentials are optimized to work around 250-280 eV. They yield reliable description for most oxides, such as VxOy, TiO2, CeO2, but fail to describe some structural details in zeolites (i.e. cell parameters, and volume).

For Hatree-Fock and hybrid functional calculations, we strictly recommend to use the standard, standard GW, or the hard potentials. For instance, the O_s potential can cause unacceptably large errors even in transition metal oxides. Generally the soft potentials are less transferable from one DFT functional to another, and often fail when exact exchange needs to be calculated.

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 potentials 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):

Element (and appendix) default cutoff ENMAX (eV) valency
H 250 1
H_h 700 1
Li 140 1
Li_sv 499 3
Na 102 1
Na_pv 260 7
Na_sv 646 9
K_pv 117 7
K_sv 259 9
Rb_pv 122 7
Rb_sv 220 9
Cs_sv 220 9
Be 248 2
Be_sv 309 4
Mg 200 2
Mg_pv 404 8
Mg_sv 495 10
Ca_pv 120 8
Ca_sv 267 10
Sr_sv 229 10
Ba_sv 187 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 lies above 3 Ry.

Element (and appendix) default cutoff ENMAX (eV) valency
Sc 155 3
Sc_sv 223 11
Fe 268 8
Fe_pv 293 14
Fe_sv 391 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 275 12
Co 268 9
Co_pv 271 15
Co_sv 390 17
Zr_sv 230 12
Rh 229 9
Rh_pv 247 15
Hf 220 4
Hf_pv 220 10
Ir 211 9
V 193 5
V_pv 264 11
V_sv 264 13
Ni 270 10
Ni_pv 368 16
Nb_pv 209 11
Nb_sv 293 13
Pd 251 10
Pd_pv 251 16
Ta 224 5
Ta_pv 224 11
Pt 230 10
Pt_pv 295 16
Cr 227 6
Cr_pv 266 12
Cr_sv 395 14
Cu 295 11
Cu_pv 369 17
Mo 225 6
Mo_pv 225 12
Mo_sv 243 14
Ag 250 11
Ag_pv 298 17
W 223 6
W_sv 223 14
Au 230 11
Mn 270 7
Mn_pv 270 13
Mn_sv 387 15
Zn 277 12
Tc 229 7
Tc_pv 264 13
Tc_sv 319 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

Element (and appendix) default cutoff ENMAX (eV) valency
B_h 700 3
B 319 3
B_s 269 3
Al 240 3
Ga 135 3
Ga_d 283 13
Ga_h 405 13
In 96 3
In_d 239 13
Tl 90 3
Tl_d 237 13
C_h 700 4
C 400 4
C_s 274 4
Si 245 4
Ge 174 4
Ge_d 310 14
Ge_h 410 14
Sn 103 4
Sn_d 241 14
Pb 98 4
Pb_d 238 14
N_h 700 5
N 400 5
N_s 280 5
P 255 5
P_h 390 5
As 209 5
As_d 289 15
Sb 172 5
Bi 105 5
Bi_d 243 15
O_h 700 6
O 400 6
O_s 283 6
S 259 6
S_h 402 6
Se 212 6
Te 175 6
Po 160 6
Po_d 265 16
F_h 773 7
F 400 7
F_s 290 7
Cl 262 7
Cl_h 409 7
Br 216 7
I 176 7
At 161 7
Ne 344 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 the presently available density functionals. In particular, partially filled f states are often incorrectly described, for instance, all f states are pinned at the Fermi-level, leading to large overbinding for Pr-Eu and Tb-Yb. The errors are largest at quarter and three-quarter filling (e.g. 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 if the f electrons form band-like (itinerant) states.

Element (and appendix) default cutoff ENMAX (eV) valency
La 219 11
Ac 172 11
Ce 273 12
Tb 265 19
Th 247 12
Th_s 169 10
Pr 273 13
Dy 255 20
Pa 252 13
Pa_s 193 11
Nd 253 14
Ho 257 21
U 253 14
U_s 209 14
Pm 259 15
Er 298 22
Np 254 15
Np_s 208 15
Sm 258 16
Tm 257 23
Pu 254 16
Pu_s 208 16
Eu 250 17
Yb 253 24
Am 256 17
Gd 256 18
Lu 256 25

For some elements soft versions (_s) are available, as well. The semi-core p states are always treated as valence states, whereas the semi-core s states are treated as valence states only in the standard potentials. For most applications (oxides, sulfides), the standard version should be used, since the soft versions might result in s ghost-states close to the Fermi-level (e.g. Ce_s in ceria). For calculations on inter-metallic compounds the soft versions are, however, sufficiently accurate.

In addition, special GGA potential are supplied for Ce-Lu, in which f electrons are kept frozen in the core (standard model for the treatment of localised f electrons). The number of f electrons in the core equals the total number of valence electrons minus the formal valency. For instance: according to the periodic table Sm has a total of 8 valence electrons (6f electrons and 2s electrons). In most compounds Sm, however, adopts a valency of 3, hence 5f electrons are placed in the core, when the pseudopotential is generated (the corresponding potential can be found in the directory Sm_3). The formal valency n is indicted by _n, where n is either 3 or 2. Ce_3 is for instance a Ce potential for trivalent Ce (for tetravalent Ce the standard potential should be used).

Element (and appendix) default cutoff ENMAX (eV) valency
Ce_3 177 11
Tb_3 156 9
Pr_3 182 11
Dy_3 156 9
Nd_3 184 11
Ho_3 154 9
Pm_3 177 11
Er_3 155 9
Er_2 120 8
Sm_3 177 11
Tm_3 149 9
Eu_3 129 9
Eu_2 99 8
Yb_3 188 9
Yb_2 113 8
Gd_3 154 9
Lu_3 155 9

References