scf.Hubbard.U on # on|off, default=off scf.DFTU.Type 2 # 1:Simplified(Dudarev)|2:General, default=1
scf.DFTU.Type=1corresponds to the so-called 'simplified rotationally invariant form' by Dudarev et al.  as implemented in the previous versions of OpenMX , where only (Hubbard ) plays a role. In more general DFT+ schemes, not only but also (Hund's coupling ) are used as input parameters. Note that the keyword 'scf.SpinPolarization' should be always switched on, meaning that 'on' or 'nc' has to be specified, whenever the DFT+U methods are used.
The occupation number operator  is specified by the following keyword:
scf.Hubbard.Occupation dual # onsite|full|dual, default=dualAmong three occupation number operators, only the dual operator satisfies a sum rule that the trace of occupation number matrix gives the total number of electrons. For the details of the operators onsite, full, and dual, see Ref. .
The and values in eV on each orbital of species defined by
<Definition.of.Atomic.Species Ni Ni6.0S-s2p2d2f1 Ni_CA13S O O5.0-s2p2d1 O_CA13 Definition.of.Atomic.Species>are specified by
<Hubbard.U.values # eV Ni 1s 0.0 2s 0.0 1p 0.0 2p 0.0 1d 5.0 2d 0.0 1f 0.0 O 1s 0.0 2s 0.0 1p 0.0 2p 0.0 1d 0.0 Hubbard.U.values>and
<Hund.J.values # eV Ni 1s 0.0 2s 0.0 1p 0.0 2p 0.0 1d 0.9 2d 0.0 1f 0.0 O 1s 0.0 2s 0.0 1p 0.0 2p 0.0 1d 0.0 Hund.J.values>The beginning of the description must be
<Hund.J.values), and the last of the description must be
Hund.J.values>) for (). For all the basis orbitals, you have to give and values in eV as in the above format. The '1s' and '2s' mean the first and second -orbital, and the number behind '1s' is the (or ) value for the first -orbital. The same rule is applied to - and -orbitals. When
scf.DFTU.Type=1, only values are read and thus users do not need to specify values.