[Wien] large E-cut is necessary in SO?

[Chur Allen]

Dear wien users:
     I am doing a calculation with PbTe spin orbit coupling. I calculated 
their energy gap.I used 3 methods as follows:
1. set p-1/2 zero, E-cut is 3.0
2. set p-1/2 zero, E-cut is 10.0
3.add p-1/2 LO for Pb. E-cut is 3.0

  in my opinion, the 2 and 3 should be better and they are almost the 
same.However,their results are only a half of the 1, which are close to the 
experimental value.but I  think the 1 is just a coincidence.Which result 
should i believe?why?Thanks for your suggestions.
btw. The DOS of 1 and 3 is different, a spliting of d-DOS for Pb is noticed.

best regards

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