De Lange, Jurgens HendrikCukrowski, Ignacy2017-06-272017-05De Lange, J.H. & Cukrowski, I. 2017, 'Toward deformation densities for intramolecular interactions without radical reference states using the fragment, atom, localized, delocalized, and interatomic (FALDI) charge density decomposition scheme', Journal of Computational Chemistry, vol. 38, no. 13, pp. 981-997.1096-987X (online)0192-8651 (print)10.1002/jcc.24772http://hdl.handle.net/2263/61112A novel approach for calculating deformation densities is presented, which enables to calculate the deformation density resulting from a change between two chemical states, typically conformers, without the need for radical fragments. The Fragment, Atom, Localized, Delocalized, and Interatomic (FALDI) charge density decomposition scheme is introduced, which is applicable to static electron densities (FALDI-ED), conformational deformation densities (FALDI-DD) as well as orthodox fragment-based deformation densities. The formation of an intramolecular NH⋅⋅⋅N interaction in protonated ethylene diamine is used as a case study where the FALDI-based conformational deformation densities (with atomic or fragment resolution) are compared with an orthodox EDA-based approach. Atomic and fragment deformation densities revealed in real-space details that (i) pointed at the origin of density changes associated with the intramolecular H-bond formation and (ii) fully support the IUPAC H-bond representation. The FALDI scheme is equally applicable to intra- and intermolecular interactions.English© 2017 Wiley Periodicals, Inc. This is the pre-peer reviewed version of the following article : 'Toward deformation densities for intramolecular interactions without radical reference states using the fragment, atom, localized, delocalized, and interatomic (FALDI) charge density decomposition scheme', Journal of Computational Chemistry, vol. 38, no. 13, pp. 981-997, 2017. doi : 10.1002/jcc.24772. The definite version is available at : http://onlinelibrary.wiley.comjournal/10.1111/(ISSN)1365-2729.Deformation densityFragment, atom, localized, delocalized, and interatomic (FALDI)FALDI charge density decomposition schemeDomain averaged Fermi hole (DAFH)Intramolecular interactionsComputational chemistryPostprint Article