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7.11 ICHARG-tag

 

displaymath4531

Default:
if ISTART=0 2
else 0
This flag determines how to construct the 'initial' charge density.
0
Calculate charge density from initial wave functions.

Mind: if ISTART is internally reset due to an invalid WAVECAR-file the parameter ICHARG will be set to ICHARG=2.

1
Read the charge density from file CHGCAR, and extrapolate from old positions to new positions using a linear combination of atomic charge densities
2
Take superposition of atomic charge densities

+10
non-selfconsistent calculation

Adding ten to the value of ICHARG (e.g. using 11,12 or the less convenient value 10) means that the charge density will be kept constant during the whole electronic minimization.

There are several reasons why to use this flag:

The initial charge density is of importance in the following cases:


next up previous contents
Next: 7.12 INIWAV-tag Up: 7 The INCAR File Previous: 7.10 ISTART-tag

MASTER USER VASP
Mon Mar 29 10:38:29 MEST 1999