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New ladder-type chromophores, the quaterrylenebis(dicarboxdiimide)s 2, 18 and 23, have been synthesised which, despite their extended p-system, exhibit good solubility in organic solvents and film forming properties when adequately substituted. These unprecedented dyes, which absorb and even emit light in the NIR window, are also characterized by oustanding chemical, thermal and photochemical stability with regard to their absorption range. The potential formation of J-aggregates in strongly acidic media has been investigated and has been ruled out by combined 1H NMR and UV-VIS-NIR spectroscopy experiments. In addition, their photophysical and electrochemical characteristics have been explored and are discussed. Results and discussionlenebis(dicarboximide)s, namely the terryleneimides 7,815 and Synthesis The synthetic pathway to quaterrylenebis(dicarboximide)s 2a,b †Chercheur Qualifie ´au Fonds National de le Recherche Scientifique, is illustrated in Scheme 1. The key building block for the synthesis Universite ´libre de Bruxelles, Chimie Macromole ´culaire, CP 206/1, of quaterrylenebis(dicarboximide)s is the N-substituted pery-Boulevard du Triomphe,

The results of elastic, quasielastic, and inelastic neutron-scattering studies on polycrystalline CeM2Ge2 (M=Ag, Au, and Ru) are presented. All compounds reveal long-range magnetic order at low temperatures. Ferromagnetic (M=Ru), antiferromagnetic (M=Au), and incommensurate (M=Ag) structures were detected. Using time-of-flight (TOF) techniques, the crystalline electric-field splittings were determined. With high-resolution TOF experiments the temperature and wave-vector dependence of the magnetic relaxation rate was studied. Korringa-like behavior was found for the Au and Ru compounds.In CeAgzGe2 the temperature dependence of the magnetic relaxation rate exhibits a square-root dependence at high temperatures and shows a residual linewidth for low T. This behavior can be explained by strong hybridization effects of the f electrons with the delocalized band states which are active in heavy fermion systems. Previous results in CeCu2Ge2 and CeNi&Ge& are included, whenever necessary. Detailed comparison is made with results obtained in the disilicides.