If you are still confused, please check Section 3.21.6 of Multiwfn manual to gain basic knowledges about NTO method.
]]>But when I repeat the process again I am not getting energy gap. HOMO and LUMO have same energies
55(H ) --> Charge: 1.000000 x,y,z(Bohr): -11.214523 -3.650781 0.598930
56(H ) --> Charge: 1.000000 x,y,z(Bohr): -6.178762 1.802666 -4.288639
57(H ) --> Charge: 1.000000 x,y,z(Bohr): -0.057032 -5.519588 2.665837
Note: Orbital 105 is HOMO, energy: 0.978720 a.u. 26.632331 eV
Orbital 106 is LUMO, energy: 0.978720 a.u. 26.632331 eV
HOMO-LUMO gap: 0.000000 a.u. 0.000000 eV 0.000000 kJ/mol
What may be the reason?
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