[Wien] ghost band

[Stefaan Cottenier]

> , I don’t understand why LO is added in case.in1 file (in what case we 
> should add the LO), and how to define the energy for this LO. Can 
> anyone explain to me?

Most of the LO's are decided upon automatically, and this is fairly 
robust. What you probably refer to is adding extra LO's at high 
energies. This is needed when you are interested in the DOS of 
unoccupied states. This enhances precision, but is rarely necessary to 
get a case converged. I don't think your troubles are due to this.

> Currently I tried to run an interface LiTaO3/RuO2. Everything was fine 
> during initialization. When come to scf calculation, the dayfile 
> message shown: /INFO: K-LIST in CLMSUM changed in MIXER xxx /after 
> Lapw1,and QTL-B value shown after Lapw2.The calculation was then stop 
> with message “lapw2 crashed!” at cycle 2. In this case I used RmtKmax 
> 5 with Kmesh 50. I understand that we can ignore the K-list message in 
> cycle 1. So I presume that the ghostband have caused the problem 
> (QTL-B value >5%). Thus, I tried to change all E-parameter from 0.3 Ry 
> to -0.04 Ry, which is 0.2 Ry below the Fermi Level and rerun the scf. 
> But it doesn’t help. The same error occurred again.

Re-initialize from scratch in a new, clean directory to make sure that 
this k-list message is really there. It could be a result of messing up 
something while playing with the initialization. If it still crashes 
after lapw2, look at the bottom of case.scf2 to see which state triggers 
the qtl-b problem. You will also see there to what value you have the 
change the linearization energy of that state.

> I tried to switch “in1new 5”, but this time the calculation even stop 
> at 1^st cycle. Then I tried to reduce the mixing factor from 0.1 to 
> 0.01, with restart the dstart. The calculation then stopped at cycle 4 
> after LAPW1, with empty error file.

I assume you are making all these changes in the same directory? If you 
do not know exactly what you are doing, it's easy to mess things up. For 
such a big interface supercell, I would definitely start with a mixing 
value around 0.01. Try it, in a clean directory. If there is really no 
error message, look in case.dayfile and to your 'screen' output to find 
out why it stopped (queue problem?)

> Another thing I want to note here is I found that there is no core for 
> Lithium, where from case.scfc file, I noticed that the core for 
> Lithium is 0.0000Ry. I am not sure whether this is the cause for the 
> problem or not. Did anyone face the same problem before?

That is no problem. The 1s level of Li is at -3.8 Ry, the 2s is at -0.2 
Ry. With the default separation energy of -6 Ry, both fall in the 
valence region. There are no core states for Li.

Stefaan


Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm