## energy hypersurface (potential energy surface) (PES)

https://doi.org/10.1351/goldbook.ET07029
The notion of hypersurface is used to stress the multidimensionality of PESs. In a molecular system consisting of $$N$$ atomic nuclei, the number of the independent coordinates that fully determine the PES is equal to $$3\ N-6$$ (or $$3\ N-5$$ if the system is linear).
Source:
PAC, 1999, 71, 1919. (Glossary of terms used in theoretical organic chemistry) on page 1938 [Terms] [Paper]