LDAUTYPE: Difference between revisions
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*{{TAG|LDAUTYPE}}=2: The simplified (rotationally invariant) approach to the DFT+U, introduced by Dudarev ''et al.''{{cite|dudarev:prb:98}} | *{{TAG|LDAUTYPE}}=2: The simplified (rotationally invariant) approach to the DFT+U, introduced by Dudarev ''et al.''{{cite|dudarev:prb:98}} | ||
*{{TAG|LDAUTYPE}}=4: same as {{TAG|LDAUTYPE}}=1, but without exchange splitting. | *{{TAG|LDAUTYPE}}=4: same as {{TAG|LDAUTYPE}}=1, but without exchange splitting. |
Revision as of 14:20, 18 October 2022
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=2: The simplified (rotationally invariant) approach to the DFT+U, introduced by Dudarev et al.[2]
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 and (LDAUU and LDAUJ, respectively). It is therefore not meaningful to compare the total energies resulting from calculations with different and/or , or 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 =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 ( elements) and 6 ( elements).
Related tags and articles
LDAU, LDAUL, LDAUU, LDAUJ, LDAUPRINT, LMAXMIX, DFT+U: formalism