Optical and magnetic resonance spectra of linear chain excitons

The zero-field optically detected magnetic resonance (ODMR) spectra for the lowest triplet state of pairs of 1,4- dibromonaphthalene molecules is reported. The structures of the three magnetic transitions for both monomers and dimers were interpreted by incorporating in the spin hamiltonians the fine structure, hyperfine structure, and quadrupole interactions. The resonance multiplet emission from the different clusters of dibromonaphthalene-h_6 in the perdeutrohost, at different guest concentrations, gave the pairwise triplet excitation transfer matrix element β_c = 6.2 ± 0.3 cm^(−1) for the 0—0 transition. The luminescence results suggest a role for energy transport between the different clusters in the chain in the thermalization process for excitations