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<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">Dear QE-users/Developers,</div>
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<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">In DFT+U calculation of an AFM pure system, I used an input file in which I had not used "occupation" card, but only a few bands more than half of the number of electrons. Then, the SCF run was successful, and in the output I get both HOMO and LUMO values correctly aligned, i.e., E_LUMO > E_HOMO.</div>
<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">However, when I add a metallic impurity (without changing the other parameters), the SCF run successfuly ends and in the output now I get E_HOMO > E_LUMO (!!).</div>
<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">I do not know how to interpret this result. Is there any miscalculation?</div>
<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">Any comments is highly appreciated.</div>
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<div style="font-size: 16px; font-family: Tahoma; color: rgb(0, 0, 0); font-weight: 400; font-style: normal;">Best regards,</div>
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<div style="font-family: Tahoma; color: rgb(0, 0, 0); font-size: 16px; font-weight: 400; font-style: normal;">Mahmoud Payami</div>
AEOI, Tehran, Iran
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<div style="font-family: Tahoma; color: rgb(0, 0, 0); font-size: 16px; font-weight: 400; font-style: normal;">Email: mpayami@aeoi.org.ir</div>
<div style="font-family: Tahoma; color: rgb(0, 0, 0); font-size: 16px; font-weight: 400; font-style: normal;">Phone: +98 (0)21 82066504</div>
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