| Abstract
| - The syntheses and electrooptic properties of a new family of nonlinear optical chromophoresare reported. These species feature an ethyne-elaborated, highly polarizable porphyrinic component andmetal polypyridyl complexes that serve as integral donor and acceptor elements. Examples of thisstructural motif include ruthenium(II) [5-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))-10,20-bis(2‘,6‘-bis(3,3-dimethyl-1-butyloxy)phenyl)porphinato]zinc(II)-(2,2‘;6‘,2‘ ‘-terpyridine)2+ bis-hexafluorophosphate (Ru-PZn);osmium(II) [5-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))-10,20-bis(2‘,6‘-bis(3,3-dimethyl-1-butyloxy)phenyl)porphinato]zinc(II)-(2,2‘;6‘,2‘ ‘-terpyridine)2+ bis-hexafluorophosphate (Os-PZn); ruthenium(II) [5-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))-15-(4‘-nitrophenyl)ethynyl-10,20-bis(2‘,6‘-bis(3,3-dimethyl-1-butyloxy)phen-yl)porphinato]zinc(II)-(2,2‘;6‘,2‘ ‘-terpyridine)2+ bis-hexafluorophosphate (Ru-PZn-A); osmium(II) [5-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))-15-(4‘-nitrophenyl)ethynyl-10,20-bis(2‘,6‘-bis(3,3-dimethyl-1-butyloxy)phenyl)porphinato]zinc(II)−(2,2‘;6‘,2‘ ‘-terpyridine)2+ bis-hexafluorophosphate (Os-PZn-A); and ruthenium(II)[5-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))osmium(II)-15-(4‘-ethynyl-(2,2‘;6‘,2‘ ‘-terpyridinyl))-10,20-bis(2‘,6‘-bis(3,3-dimethyl-1-butyloxy)phenyl)porphinato]zinc(II)-bis(2,2‘;6‘,2‘ ‘-terpyridine)4+ tetrakis-hexafluorophosphate (Ru-PZn-Os). The frequency dependence of the dynamic hyperpolarizability of thesecompounds was determined from hyperRayleigh light scattering (HRS) measurements carried out atfundamental incident irradiation wavelengths (λinc) of 800, 1064, and 1300 nm. These data show that (i)coupled oscillator photophysics and metal-mediated cross-coupling can be exploited to elaborate high β0supermolecules that exhibit significant excited-state electronic communication between their respectivepigment building blocks; (ii) high-stability metal polypyridyl compounds constitute an attractive alternativeto electron releasing dialkyl- and diarylamino groups, the most commonly used donor moieties in a widerange of established nonlinear optical dyes; (iii) this design strategy enables ready elaboration ofchromophores having extraordinarily large dynamic hyperpolarizabilities (βλ values) at telecommunicationrelevant wavelengths; and (iv) porphyrin B- and Q-state-derived static hyperpolarizabilities (β0 values) canbe designed to have the same or opposite sign in these species, thus providing a new means to regulatethe magnitude of λinc-specific dynamic hyperpolarizabilities.
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