Developers Manual:ABINIT

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.hgh file format

The format number 3 for ABINIT pseudopotentials allows the use of the pseudopotentials from the Hartwigsen et al. 1998 article with a few extra header lines added to the file. The local part of the pseudopotential is given by: V_{loc}(r)=-\frac{Z_{ion}}{r}\mathrm{erf}\left(\frac{r}{\sqrt{2}r_{loc}}\right)+\exp{\left[-\frac{1}{2}\left(\frac{r}{r_{loc}}\right)^2\right]\left[C_1+C_2\left(\frac{r}{r_{loc}}\right)^2+C_3\left(\frac{r}{r_{loc}}\right)^4+C_4\left(\frac{r}{r_{loc}}\right)^6\right]}, where \mathrm{erf}{()} is the error function.

The nonlocal contribution to the pseudopotential is given by: \Delta{}V_l(r)=\sum_{i=1}^{3}\sum_{j=1}^{3}p_i^l(r)h_{i,j}^lp_j^l(r) where the projectors p_i^l(r) are Gaussians of the form: p_i^l(r)=\frac{\sqrt{2}r^{l+2(i-1)}\exp{\left[-\frac{1}{2}\left(\frac{r}{r_{loc}}\right)^2\right]}}{r_l^{l+(4i-1)/2}\sqrt{\Gamma\left(l+(4i-1)/2\right)}} satisfying the normalization condition \int_0^{\infty}p_i^l(r)p_i^l(r)r^2dr=1


Line Column Descritpion

1 title line will be printed without modification in the output of ABINIT
2 1 Z the atomic number
2 Z^{ion} number of valence electrons.
3 981030 the date of generation.
3 1 3 the pseudopotential format, always 3 for format 3 ;-)
2 i^{XC} the exchange and correlation functional used to generate the pseudopotential
3 l_{max} maximum angular momentum of the wavefunctions
4 0 angular momentum, not used
5 2001 number of radial mesh points, not used
6 0 prefactor of a harmonic well, not used
4 1 r_{loc} radius
2 C_1
3 C_2
4 C_3
5 C_4

.fhi file format

The format number 6 for ABINIT pseudopotentials allows the use of pseudopotentials generated from by the fhi98PP code with a few extra header lines added to the file.


Line Column Descritpion

1 title line will be printed without modification in the output of ABINIT
2 1 Z the atomic number
2 Z^{ion} number of valence electrons.
3 981030 the date of generation.
3 1 6 the pseudopotential format, always 6 for format 6 ;-)
2 i^{XC} the exchange and correlation functional used to generate the pseudopotential
3 l_{max} maximum angular momentum of the wavefunctions
4 l_{loc} angular momentum of the potential to be used as local pseudopotential
5 m_{max} number of radial mesh points
6 r_{well}^2 prefactor of a harmonic well, not used
4 1 r_{chrg} radius at which the core charge vanish (in a.u.)
2 f_{chrg} amplitude of core charge, has no physical meaning in fhi98PP scheme of core correction
3 q_{chrg} integrated model core charge, not actually used by ABINIT
5 to 7 unused

.cpi file follows. Z^{ion}, l_{max} and m_{max} must match

Exchange and Correlation

ABINIT uses the Pseudopotentials generated by the fhi98PP program with a few extra header lines added to the file. But the Exchange and Correlation Code differs.


Code Exchange Correlation Correction

0 - - -
1 TeterPade1993 TeterPade1993 -
2 PerdewZunger1981 PerdewZunger1981 -
3 Teter1991 Teter1991 -
4 Wigner1934 Wigner1934 -
5 HedinLundqvist1971 HedinLundqvist1971 -
6 Slater - -
7 PerdewWang1992 PerdewWang1992 -
8 PerdewWang1992 - -
9 PerdewWang1992 GellMannBrueckner1957 -
10 - GellMannBrueckner1957 -
11 PerdewBurkeErnzerhof1996 PerdewBurkeErnzerhof1996 -
12 PerdewBurkeErnzerhof1996 - -
13 PerdewWang1992 PerdewWang1992 LeeuwenBaerends1994
14 ZhangYang1998 ZhangYang1998 -
15 HammerHansenNorskov1999 HammerHansenNorskov1999 -
16 Hamprecht1998 Hamprecht1998 -
20 FermiAmaldi1934 FermiAmaldi1934 -
21 FermiAmaldi1934 FermiAmaldi1934 -
22 FermiAmaldi1934 FermiAmaldi1934 -
30 Slater - -
31 Slater VoskoWilkNusair1980 -
32 Slater PerdewZunger1981 -
33 Slater PerdewWang1992 -
34 Slater Attaccalite2002 -

references

S. Goedecker, M. Teter, and J. Hutter. Separable dual-space Gaussian pseudopotentials. Physical Review B, 54(3):1703-1710, July 1996.

C. Hartwigsen, S. Goedecker and J. Hutter. Relativistic separable dual-space Gaussian pseudopotentials from H to Rn. Physical Review B, 58(7):3641-3662, August 1998.

The ~ABINIT/Infos/Psp_infos/psp3.info file.

The ~ABINIT/Infos/Psp_infos/psp6.info file.