My Community

Hello all,

I am currently trying to do some calculations on the absorption spectrum of heterostructures, I was hoping to take my calculations past the LOPTICS level to the ALGO=CHI level to incorporate local fields.

I can do the calculations, and they finish, and they seem to get a relatively reasonable answer for epsilon2, but for epsilon1 my vasprun.xml file generally looks like this...

<real>
<array>
<dimension dim="1">gridpoints</dimension>
<field>energy</field>
<field>xx</field>
<field>yy</field>
<field>zz</field>
<field>xy</field>
<field>yz</field>
<field>zx</field>
<set>
<r> 0.0000 ********** ********** ********** 16756.8771 33711.8830 15729.2707 </r>
<r> 0.1711 ********** ********** ********** 16764.8528 33728.0237 15736.7524 </r>
<r> 0.3421 ********** ********** ********** 16788.9244 33776.6417 15759.3362 </r>
<r> 0.5131 ********** ********** ********** 16829.2200 33858.0212 15797.1598 </r>
<r> 0.6840 ********** ********** ********** 16885.9588 33972.6491 15850.4641 </r>
<r> 0.8548 ********** ********** ********** 16959.4562 34121.2376 15919.6017 </r>
<r> 1.0255 ********** ********** ********** 17050.1229 34304.7461 16005.0532 </r>
<r> 1.1961 ********** ********** ********** 17158.4680 34524.4340 16107.4581 </r>
<r> 1.3665 ********** ********** ********** 17285.0987 34781.9533 16227.6615 </r>
<r> 1.5367 ********** ********** ********** 17430.7462 35079.6108 16366.8516 </r>
<r> 1.7067 ********** ********** ********** 17595.9998 35420.4573 16526.6258 </r>
<r> 1.8764 ********** ********** ********** 17782.0791 35810.7160 16710.1903 </r>
<r> 2.0459 ********** ********** ********** 17986.4555 36257.8843 16920.9507 </r>
<r> 2.2151 ********** ********** ********** 18193.4988 36748.9508 17144.3230 </r>
<r> 2.3841 ********** ********** ********** 18457.7312 37080.5334 17272.1895 </r>
<r> 2.5527 ********** ********** ********** 18832.3869 37530.5717 17497.0883 </r>
<r> 2.7209 ********** ********** ********** 19063.8969 38099.2550 17722.1745 </r>
<r> 2.8888 ********** ********** ********** 19349.5901 38734.7473 17988.0998 </r>
<r> 3.0564 ********** ********** ********** 19813.6112 39543.5854 18406.5625 </r>
<r> 3.2236 ********** ********** ********** 20206.2264 40442.5097 18828.9537 </r>
<r> 3.3903 ********** ********** ********** 20480.9582 41369.4199 19196.7634 </r>
<r> 3.5567 ********** ********** ********** 20882.7787 42321.4282 19598.7583 </r>
<r> 3.7226 ********** ********** ********** 21436.6770 43371.3416 20088.2936 </r>
<r> 3.8880 ********** ********** ********** 22025.4233 44527.9437 20631.8196 </r>
<r> 4.0530 ********** ********** ********** 22649.0390 45793.1897 21218.3351 </r>
<r> 4.2175 ********** ********** ********** 23366.5835 47212.4766 21851.3321 </r>
<r> 4.3816 ********** ********** ********** 24178.6193 48797.6685 22554.4401 </r>
<r> 4.5452 ********** ********** ********** 25070.9905 50563.0362 23342.9619 </r>
<r> 4.7082 ********** ********** ********** 26053.0424 52513.4140 24203.8586 </r>
<r> 4.8708 ********** ********** ********** 27137.2129 54682.3111 25177.5266 </r>
<r> 5.0328 ********** ********** ********** 28333.1664 57117.8983 26313.4360 </r>
<r> 5.1943 ********** ********** ********** 29674.3522 59838.7165 27540.3911 </r>
<r> 5.3553 ********** ********** ********** 31175.4401 62899.0200 28890.7454 </r>
<r> 5.5157 ********** ********** ********** 32897.7631 66403.5817 30430.5692 </r>
<r> 5.6756 ********** ********** ********** 34903.7549 70465.7707 32213.5633 </r>
<r> 5.8349 ********** ********** ********** 37221.3150 75174.0977 34259.1962 </r>
<r> 5.9937 ********** ********** ********** 39933.9352 80700.0365 36632.5467 </r>
<r> 6.1520 ********** ********** ********** 43317.3046 87443.1052 39578.4465 </r>
<r> 6.3097 ********** ********** ********** 47414.3915 95623.4861 43090.1305 </r>

And so on and so forth up until about 50 eV

I gather those ****** entries are values too high to be displayed in the .xml file. However, I am unsure of what I can do to make these calculations produce reasonable values.

Here is the INCAR for this run.

SYSTEM = Si.p-uc.pbe.lf.7: Local Fields Run
Starting Parameters
ISTART = 0
ICHARG = 2
LREAL = .FALSE.
Electronic Relaxation Parameters
ALGO = CHI
NELM = 1
EDIFF = 1e-8
Ionic Relaxation Parameters
Job Parameters
ISMEAR = 0
SIGMA = 0.05
NBANDS = 64
NEDOS = 9999
ENCUT = 300
Added Parameters
LOPTICS = .TRUE.
NOMEGA = 250
PRECFOCK = N
LRPA = .TRUE.

Any advice would be greatly appreciated.

Hi,

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