LDAUTYPE

LDAUTYPE = 1 | 2 | 4
Default: LDAUTYPE = 2

Description: LDAUTYPE specifies the DFT+U variant that will be used.

Three variants of the DFT+U approach are available in VASP (a brief overview is given here):

LDAUTYPE=1: The rotationally invariant DFT+U introduced by Liechtenstein et al.^[1]

LDAUTYPE=2: The simplified (rotationally invariant) approach to the DFT+U, introduced by Dudarev et al.^[2]

This flavour of DFT+U is of the following form:

LDAUTYPE=4: same as LDAUTYPE=1, but without exchange splitting.

Warning: it is important to be aware of the fact that when using the DFT+U, in general the total energy will depend on the parameters $U$ and $J$ (LDAUU and LDAUJ, respectively). It is therefore not meaningful to compare the total energies resulting from calculations with different $U$ and/or $J$ , or $U-J$ and in case of Dudarev's approach (LDAUTYPE=2).

Note on band structure calculation: the CHGCAR file contains only information up to angular momentum quantum number $l$ =LMAXMIX for the on-site PAW occupancy matrices. When the CHGCAR file is read and kept fixed in the course of the calculations (ICHARG=11), the results will be necessarily not identical to a self-consistent run. The deviations are often large for DFT+U calculations. For the calculation of band structures within the DFT+U approach, it is hence strictly required to increase LMAXMIX to 4 ( $d$ elements) and 6 ( $f$ elements).

References

[liechtenstein:prb:95-1] A. I. Liechtenstein, V. I. Anisimov, and J. Zaanen, Phys. Rev. B 52, R5467 (1995).

[dudarev:prb:98-2] S. L. Dudarev, G. A. Botton, S. Y. Savrasov, C. J. Humphreys, and A. P. Sutton, Phys. Rev. B 57, 1505 (1998).

[1]

[2]

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