(a) Hybridization of the basic dipolar surface plasmons between two adjacent nanorods : (Center) Energy splitting of the fundamental mode of a dimer antenna with the corresponding charges distribution and electric field lines in the bonding (bottom) and antibonding (top) modes; (b) EELS spectra and intensity maps on a silver nanorod dimer demonstrating the appearance of the bonding and antibonding modes : the first ones at lower energies (1.2 eV) peak at the outer extremities of the dimer (spots in positions red and blue), the second one of stronger intensity and higher energy (1.35 eV) peaks right in the gap between the rods (spot in position green). Each silver rod is 40 nm thick and 200 nm long (courtesy Z. Mafoud, Ph.D. Orsay, 2012)