- #1
Manganese
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- TL;DR Summary
- How to identify HOMO/LUMO in molecules with singly occupied orbitals?
Hello,
as the title says, how do you treat singly occupied orbitals in radical molecules, when trying to identify the HOMO and LUMOs?
In the majority of cases I stumbled upon, like O2, both the antibonding orbitals, pi*2px pi*2py, are singly occupied, so they would be considered the HOMO, with the antibonding sigma*2s being the LUMO. Same goes for other radicals that have one fully occupied orbital (eg pi*2px) and one singly occupied (eg pi*2py).
But in molecules like NO, where only one of the two antibonding orbitals is singly occupied (eg, the pi*2px OR the pi*2py), what is considered the HOMO and which the LUMO? Are both the pi*2px and pi*2py considered HOMO even if only one of them is occupied (and only by 1 e), with the sigma*2s being the LUMO? Or both the pi*2px and pi*2py are considered HOMO and LUMO at the same time (is that even possible?) Even if we call the singly occupied orbitals as SOMO, what would be the corresponding LUMO?
as the title says, how do you treat singly occupied orbitals in radical molecules, when trying to identify the HOMO and LUMOs?
In the majority of cases I stumbled upon, like O2, both the antibonding orbitals, pi*2px pi*2py, are singly occupied, so they would be considered the HOMO, with the antibonding sigma*2s being the LUMO. Same goes for other radicals that have one fully occupied orbital (eg pi*2px) and one singly occupied (eg pi*2py).
But in molecules like NO, where only one of the two antibonding orbitals is singly occupied (eg, the pi*2px OR the pi*2py), what is considered the HOMO and which the LUMO? Are both the pi*2px and pi*2py considered HOMO even if only one of them is occupied (and only by 1 e), with the sigma*2s being the LUMO? Or both the pi*2px and pi*2py are considered HOMO and LUMO at the same time (is that even possible?) Even if we call the singly occupied orbitals as SOMO, what would be the corresponding LUMO?