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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