What is the isolobal principle?
Q: What is the isolobal principle?
A: The isolobal principle (also known as isolobal analogy) is a way to predict bonding properties of organometallic compounds. It relates the structure of organic ligands that can bind to inorganic molecular fragments by comparing their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO).
Q: Who proposed the isolobal principle?
A: Roald Hoffmann proposed the isolobal principle.
Q: How does it relate to isoelectronic compounds?
A: Isolobal compounds are analogs to isoelectronic compounds that share the same number of valence electrons and structure.
Q: What did Hoffmann receive for his work on this concept?
A: For his work on the isolobal analogy, Hoffmann was awarded the Nobel Prize in Chemistry in 1981, which he shared with Kenichi Fukui.
Q: How did Hoffmann describe molecular fragments?
A: Hoffmann described molecular fragments as isolobal "if the number, symmetry properties, approximate energy and shape of the frontier orbitals and the number of electrons in them are similar – not identical, but similar."
Q: How does one use this model to predict bonding and reactivity?
A: One can predict bonding and reactivity of a lesser-known pieces from that of a better-known pieces if they have similar frontier orbitals.
Q: Does this model always work correctly?
A: No, it does fail in certain instances.
