INIMIX

INIMIX = 0 | 1 | 2
Default: INIMIX = 1

Description: Determines the functional form of the initial mixing matrix in the Broyden scheme (IMIX=4).

The initial mixing matrix might influence the convergence speed for complex situations (especially surfaces and magnetic systems), nevertheless INIMIX must not be changed from the default setting: anything which can be done with INIMIX can also be done with AMIX and BMIX, and changing AMIX and BMIX is definitely preferable.

Possible choices for INIMIX are:

INIMIX=0

Linear mixing according to the setting of AMIX

INIMIX=1

Kerker mixing (see IMIX=1) according to the settings of AMIX and BMIX.

The mixed density is given by

[math]\displaystyle{ \rho_{\rm mix}\left(G\right)=\rho_{\rm in}\left(G\right)+A \frac{G^2}{G^2+B^2}\Bigl(\rho_{\rm out}\left(G\right)-\rho_{\rm in}\left(G\right)\Bigr) }[/math]

with [math]\displaystyle{ A }[/math]=AMIX and [math]\displaystyle{ B }[/math]=BMIX

INIMIX=2

No mixing (equal to INIMIX=0 and AMIX=1, not recommended)

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