title: Notes on quantitative structure-properties relationships (QSPR) part 2: the role of the number of atoms as a molecular descriptor.
abstract: A previous analysis performed in our laboratory about the polynomial dependency of the atomic quantum self-similarity measures on the atomic number, together with recent publications on quantitative structure-properties relationships (QSPR), based on the number of molecular atoms, published by various authors, have driven us to show here that a simplified form of the fundamental quantum QSPR (QQSPR) equation, permits to theoretically demonstrate the important, but obvious, role of the number of atoms in a molecule, as a possible molecular descriptor. A discussion of the practical use of the number of atoms in QSPR is also given at the end, which also contains a discussion on the role of Ockham's razor in descriptor simplification choices.
authors.affiliation: Institut de Química Computacional, Universitat de Girona, Girona 17071, Catalonia, Spain.
authors.forename: Ramon
authors.initials: R
authors.lastname: Carbó-Dorca
authors.forename: Ana
authors.initials: A
authors.lastname: Gallegos Saliner