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AMIN

AMIN = [real]
Default: AMIN = min(0.1,AMIX,AMIX_MAG

Description: AMIN specifies the minimal mixing parameter in Kerker's[1] initial approximation to the charge dielectric function used in the Broyden[2][3]/Pulay[4] mixing scheme (IMIX=4, INIMIX=1).

Kerker's[1] initial approximation for the charge dielectric function is given by

${\displaystyle A\times \min \left({\frac {G^{2}}{G^{2}+B^{2}}},A_{{{\rm {min}}}}\right)}$

where ${\displaystyle A}$ =AMIX, ${\displaystyle B}$ =BMIX, and ${\displaystyle A_{{{\rm {min}}}}}$ =AMIN.

References

1. a b G. P. Kerker, Phys. Rev. B 23, 3082 (1981).
2. S. Blügel, PhD Thesis, RWTH Aachen (1988).
3. D. D. Johnson, Phys. Rev. B38, 12807 (1988).
4. P. Pulay, Chem. Phys. Lett. 73, 393 (1980).