What is the Difference Between HOMO and LUMO?

The terms HOMO and LUMO refer to molecular orbitals in quantum chemistry, but the search results provided do not directly address these concepts. Instead, the search results mainly discuss homologous and analogous traits in biology, which are unrelated to HOMO and LUMO.

Homologous traits share a similar embryonic origin and are inherited from a common ancestor, while analogous traits have a similar function but do not share a common ancestry. Examples of homologous structures include the bones in a whale's front flipper and the bones in a human arm, while analogous structures include the wings of a butterfly and the wings of a bird.

Comparative Table: HOMO vs LUMO

The HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) are concepts in molecular orbital theory that describe the energy levels of orbitals in a molecule. The energy difference between the HOMO and LUMO, known as the HOMO-LUMO energy gap, is an important parameter in understanding the reactivity of a molecule. Here is a table summarizing the differences between HOMO and LUMO:

The HOMO-LUMO energy gap can be calculated using density functional theory (DFT) methods. It is also possible to measure the gap using UV-Vis spectroscopy or a spectrophotometer, which can provide information about the wavelengths a compound absorbs.