Reply to the ‘Comment on “A quantitative definition of hypervalency”’ by R. D. Harcourt and T. M. Klapötke, Chem. Sci., 2016, 7, DOI: 10.1039/C5SC04866D

The Lewis and quantum mechanical theories of chemical bonding are compared and contrasted, with a view to clarifying the relationship between Harcourt’s ‘increased valence’ quantum approach and the recently proposed quantitative definition of hypervalency.

Comment on “A quantitative definition of hypervalency” by M. C. Durrant, Chem. Sci., 2015, 6, 6614

Consideration is given to (electronically) hypervalent increased-valence structures, which possess 2c–1e bonds, fractional 2c–2e bonds, and usually normal 2c–2e bonds.