在BAND中,也有类似的方法,电子采用小数分布在这些“近简并”的轨道上。关键词为:
Convergence Degenerate 0.035 End
其中Degenerate 后面的数值为“近简并”能级“宽度”,单位为a.u.。这个值越大越容易收敛,但一般而言希望它尽量的小,同时又能收敛,所以需要多次测试。在*.run文件中的格式例如:
Engine BAND Basis Type DZP End KSpace Quality Normal End SCF Iterations 100 End XC GGA BP86 End Convergence Degenerate 0.035 End EndEngine
如此,得到的电子占据分布(第二、三列为能带的最高、最低点;第四列数据为电子占据个数):
238 -0.35816 -0.35816 2.00000 239 -0.35815 -0.35815 2.00000 240 -0.35815 -0.35815 2.00000 241 -0.35231 -0.35231 1.99999 242 -0.35230 -0.35230 1.99999 243 -0.34660 -0.34660 1.99996 244 -0.34659 -0.34659 1.99996 245 -0.34292 -0.34292 1.99993 246 -0.34290 -0.34290 1.99993 247 -0.34068 -0.34068 1.99989 248 -0.34067 -0.34067 1.99989 249 -0.34066 -0.34066 1.99989 250 -0.34065 -0.34065 1.99989 251 -0.34065 -0.34065 1.99989 252 -0.34063 -0.34063 1.99989 253 -0.33456 -0.33456 1.99970 254 -0.33453 -0.33453 1.99969 255 -0.31544 -0.31544 1.99495 256 -0.31543 -0.31543 1.99495 257 -0.31543 -0.31543 1.99494 258 -0.31543 -0.31543 1.99494 259 -0.31542 -0.31542 1.99494 260 -0.31540 -0.31540 1.99493 261 -0.31348 -0.31348 1.99348 262 -0.30919 -0.30919 1.98879 263 -0.30919 -0.30919 1.98879 264 -0.30917 -0.30917 1.98877 265 -0.30917 -0.30917 1.98876 266 -0.30917 -0.30917 1.98876 267 -0.30916 -0.30916 1.98875 268 -0.30722 -0.30722 1.98579 269 -0.30722 -0.30722 1.98577 270 -0.29122 -0.29122 1.92559 271 -0.26358 -0.26358 1.61050 272 -0.26357 -0.26357 1.61037 273 -0.26356 -0.26356 1.61018 274 -0.26356 -0.26356 1.61015 275 -0.26355 -0.26355 1.61006 276 -0.26355 -0.26355 1.60998 277 -0.26306 -0.26306 1.60250 278 -0.26306 -0.26306 1.60249 279 -0.26111 -0.26111 1.57148 280 -0.26110 -0.26110 1.57138 281 -0.25937 -0.25937 1.54328 282 -0.25934 -0.25934 1.54284 283 -0.25873 -0.25873 1.53262 284 -0.25872 -0.25872 1.53248 285 -0.25872 -0.25872 1.53244 286 -0.25871 -0.25871 1.53238 287 -0.25870 -0.25870 1.53216 288 -0.25869 -0.25869 1.53205 289 -0.24710 -0.24710 1.03770 290 -0.23705 -0.23705 0.88299 291 -0.23705 -0.23705 0.88299 292 -0.23702 -0.23702 0.88261 293 -0.23702 -0.23702 0.88261 294 -0.23702 -0.23702 0.88257 295 -0.23700 -0.23700 0.88229 296 -0.23138 -0.23138 0.79290 297 -0.23136 -0.23136 0.79265 298 -0.05681 -0.05681 0.00000