MIXPRE
MIXPRE = 0 | 1 | 2 | 3
Default: MIXPRE = 1
Description: MIXPRE specifies the metric in the Broyden mixing scheme(IMIX=4).
- MIXPRE=0
- No preconditioning, metric=1
- MIXPRE=1
- "Inverse Kerker" metric with automatically determined BMIX (determined in such a way that the variation of the preconditioning weights covers a range of a factor 20)
- MIXPRE=2
- "Inverse Kerker" metric with automatically determined BMIX (determined in such a way that the variation of the preconditioning weights covers a range of a factor 200)
- MIXPRE=3 (implemented for test purposes; not recommended)
- "Inverse Kerker" metric with BMIX from INCAR, the weights for the metric are given by
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://www.vasp.at/wiki/restbase/vasp.at/v1/":): P\left(G\right)=1+{\frac {B^{2}}{G^{2}}}
- with Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://www.vasp.at/wiki/restbase/vasp.at/v1/":): B =BMIX.
The preconditioning is done only on the total charge density (i.e. up+down component) and not on the magnetization charge density (i.e. up-down component). In our experience, the introduction of a metric always improves the convergence speed. The best choice is MIXPRE=1 (i.e. the default).
Related tags and articles
IMIX, INIMIX, MAXMIX, AMIX, BMIX, AMIX_MAG, BMIX_MAG, AMIN, WC