[Wien] Problems in convergence due to application of mBj potential

[Madhav Ghimire]

Dear wien users and developers,
     I am working on some 3d TM oxides. With a normal scf cycle with or
without inclusion of U value, I got good convergence in energy and charge.
This oxide material is reported to have a bandgap of approx. 0.3 eV. In
GGA, I do not observe any gap. In the meantime even with very high value of
U, the bandgap do not open up. Because of this, I tried to implement mBj
potential  (in order to find the bandgap) both with and without inclusion
of U, but the energy and charge do not converge.
Rather even for a large number of iteration (199), the energy and charge
remains constant without convergence (shown below).

For GGA without mBj the scf cycle smoothly converges as below:
in cycle 22    ETEST: .0000236850000000   CTEST: .0038743
in cycle 23    ETEST: .0000184300000000   CTEST: .0012996
in cycle 24    ETEST: .0000174650000000   CTEST: .0006011
in cycle 25    ETEST: .0000037600000000   CTEST: .0007451
in cycle 26    ETEST: .0000016050000000   CTEST: .0001163

>   stop

while  with mBj+GGA, energy and charge convergence remains constant above
cycle 103 and could not converge as below:
in cycle 193    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 194    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 195    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 196    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 197    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 198    ETEST: .2112103950000000   CTEST: 2.0591251
in cycle 199    ETEST: .2112103950000000   CTEST: 2.0591251

>   energy in SCF NOT CONVERGED

Does anyone have experienced this type of problems. If so, please let me
know how it can be converged. I followed all the steps as described in
previous wien mail and userguid but could not solve.
Your help to solve this issue will be higly appreciated.
Thanks in advance

Madhav Ghimire

-- 
MANA, National Institute for Materials Science (NIMS)
1-1 Namiki, Tsukuba, Ibaraki, Japan
Phone: +81-29-851-3354 (ex.4115)



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-- 
MANA, National Institute for Materials Science (NIMS)
1-1 Namiki, Tsukuba, Ibaraki, Japan
Phone: +81-29-851-3354 (ex.4115)
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