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 all 1998 article with a few extra header lines added to the file.
The local part of the pseudopotential is guiven 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]},](/programs/octopus/wiki/images/math/e/0/4/e04b11721942457a1d1e68fd65882bfa.png)
where erf() is the error function.
The nonlocal contribution to the pseudopotential is guiven by:
where the projectors 
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)}}](/programs/octopus/wiki/images/math/5/1/7/517b679b18e7f4ffc5999ee12c8c5a66.png)
satisfying the normalization condition 
| Line | Column | Descritpion | |
|---|---|---|---|
| 1 | title line will be printed without modification in the output of ABINIT | ||
| 2 | 1 | Z | the atomic number |
| 2 | Zion | number of valence electrons. | |
| 3 | 981030 | the date of generation. | |
| 3 | 1 | 3 | the pseudopotential format, always 3 for format 3 ;-) |
| 2 | iXC | the exchange and correlation functional used to generate the pseudopotential | |
| 3 | lmax | 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 | rloc | radius |
| 2 | C1 | ||
| 3 | C2 | ||
| 4 | C3 | ||
| 5 | C4 | ||
.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 | Zion | number of valence electrons. | |
| 3 | 981030 | the date of generation. | |
| 3 | 1 | 6 | the pseudopotential format, always 6 for format 6 ;-) |
| 2 | iXC | the exchange and correlation functional used to generate the pseudopotential | |
| 3 | lmax | maximum angular momentum of the wavefunctions | |
| 4 | lloc | angular momentum of the potential to be used as local pseudopotential | |
| 5 | mmax | number of radial mesh points | |
| 6 |  | prefactor of a harmonic well, not used | |
| 4 | 1 | rchrg | radius at which the core charge vanish (in a.u.) |
| 2 | fchrg | amplitude of core charge, has no physical meaning in fhi98PP scheme of core correction | |
| 3 | qchrg | integrated model core charge, not actually used by ABINIT | |
| 5 to 7 | unused | ||
| .cpi file follows. Zion, lmax and mmax 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.
