Hi exciting developers and users
I want to calculate XANES spectra of phosphorene nanosheet. Based on the website tutorial, at first I should run a simple scf and find the energy of interested core level, and change species file to add local orbital.
I run a scf and the band gap is about 0.03 hartree that is reasonable, but when I remove 1S from cores and add local orbital, the band gap vanishes!
Used parameters are as below:
<groundstate
stype="Fermi Dirac"
swidth="0.001d0"
dipolecorrection="true"
rgkmax="8"
ngridk="10 10 1"
gmaxvr="14.0"
xctype="GGA_PBE"
nempty="15"/>
and the changed species file of phosphorus:
<?xml version="1.0" encoding="UTF-8"?>
<spdb xsi:noNamespaceSchemaLocation="../../xml/species.xsd" xmlns:xsi="Removed/2001/XMLSchema-instance">
<sp chemicalSymbol="P" name="phosphorus" z="-15.0000" mass="56461.71408">
<muffinTin rmin="0.100000E-04" radius="2.0000" rinf="22.3534" radialmeshPoints="300"/>
<atomicState n="1" l="0" kappa="1" occ="2.00000" core="false"/>
<atomicState n="2" l="0" kappa="1" occ="2.00000" core="true"/>
<atomicState n="2" l="1" kappa="1" occ="2.00000" core="true"/>
<atomicState n="2" l="1" kappa="2" occ="4.00000" core="true"/>
<atomicState n="3" l="0" kappa="1" occ="2.00000" core="false"/>
<atomicState n="3" l="1" kappa="1" occ="1.00000" core="false"/>
<atomicState n="3" l="1" kappa="2" occ="2.00000" core="false"/>
<basis>
<default type="lapw" trialEnergy="0.1500" searchE="false"/>
<custom l="0" type="apw+lo" trialEnergy="0.1500" searchE="true"/>
<custom l="1" type="apw+lo" trialEnergy="0.1500" searchE="true"/>
<!-- Here below a local orbital is added for the state 1s -->
<lo l="0">
<wf matchingOrder="0" trialEnergy="0.1500" searchE="false"/>
<wf matchingOrder="1" trialEnergy="0.1500" searchE="false"/>
<wf matchingOrder="0" trialEnergy="-76.50" searchE="true"/>
</lo>
</basis>
<!-- Exciting code version: Lithium -->
<!-- Generation Scheme: simple -->
</sp>
</spdb>
Can anyone help me to solve the gap problem? I changed K points, gmaxvar,epsband, deband, rgkmax, stype and swidth; but there was no improvement.
(While this problem does not exist with using ELK code.)
Best wishes