Question

What is `"VSEPR"`? Who originated the treatment?

Answer 1

`"Valence Shell Electron Pair Repulsion Theory"`, `"vesper"` for short.........

Explanation:

See this old answer...........

The key idea of `"vesper"` is that electron pairs around a central atom REPEL each other. The shapes adopted around the central atom correspond to the shapes of the classic Platonic Solids, and thus electron pair and molecular geometry are based on these shapes. There is some info in the links, and there will be more in your text.

AS to its originators, Ron Gillespie, and Ron Nyholm, are credited with the theory, which they jointly developed in the 1950's-1960's. It is now a staple of undergraduate inorganic chemistry.