return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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Comparison of Koopmans' theorem (HOMO energy approximates ionzation energy)

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The following pages display the differences between the experimental ionzation energy and the energy of the HOMO (highest occupied molecular orbital) for a given molecule. Koopmans' theorem states that the HOMO energy approximates the vertical ionization energy.

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Species in the CCCBDB