Dear Steven and All:
        I have a question about the MPB program.I get a gap 0.25% from band 5 
to band 6 when I set the num-bands 8.  I want to see if it has a high order 
gap.So I set the num-bands 10.I get a 5->6 gap 0.25%,a 8->9 gap 1.48%.Again I 
set num-bands 12 ,get 
5->6 gap  17.67%  8->9 gap 1.48%. I checked this 5->6 gap and found it's a 
false gap because two bands cross.I increased num-bands to 15,this time the 
8->9 gap disappeared.I got this list:
num-bands  gap 5->6   gap 8->9
 8            0.25%         /
 10             0.25%        1.48%
 12             17.67%      1.48%
 15             0.25%         /
 18             0.25%        1.90%
 20             0.25%        1.48%
I'm confusing now.Which result can I trust? How to define a proper "num-bands"?




bigbigfat
2007-04-20
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