University of KashanIranian Journal of Mathematical Chemistry2228-64893120120201Centric Connectivity Index by Shell Matrices3543520010.22052/ijmc.2012.5200ENM. V.DiudeaBabes-Bolyai UniversityJournal Article20120110Relative centricity RC values of vertices/atoms are calculated within the Distance Detour and Cluj-Distance criteria on their corresponding Shell transforms. The vertex RC distribution in a molecular graph gives atom equivalence classes, useful in interpretation of NMR spectra. Timed by vertex valences, RC provides a new index, called Centric Connectivity CC, which can be useful in the topological characterization of graphs and in QSAR/QSPR studies.