Bichromophoric Paracyclophanes:  Models for Interchromophore Delocalization

Abstract

The electronic delocalization between chromophores in the solid is an important parameter to optimize when designing organic materials for optoelectronic applications. The [2.2]paracyclophane framework allows for the synthesis of well-defined, nonfluxional molecules that bring together two chromophores into close proximity. From the photophysical properties of these molecules we can examine how the chromophore conjugation length, their relative orientation, and the regiochemistry of contact affects the electronic delocalization between the two subunits.

Probing π-coupling in molecular junctions

“…Although it can be argued that the HOMO-1 orbital is probably more important to charge transport because it has a larger electron density on the terminal Au atoms, and hence better coupling to the metal electrodes, both orbitals undoubtedly contribute to the measured charge transport. The calculated electronic structure for 2 bound to two Au atoms, demonstrates that the low-lying through-space delocalized state (11)(12)(13)(14) can effectively facilitate charge transport in a molecular junction.…”

“…1). It is known that the optical properties of well-defined, linked conjugated oligomers such as 2 are often perturbed by transannular extension of conjugation (11)(12)(13)(14). Although these previous optical measurements have been used to determine the extent of through-space delocalization, nothing is known about how this arrangement influences the conductance of such molecules.…”

Photophysical Studies on the Mono- and Dichromophoric Hemicyanine Dyes I. Photoelectric Conversion from the Dye Modified ITO Electrodes

“…This has not happened to many dimers reported before. [21][22][23] Having observed the interesting relationships between their structures and the photophysical properties, we propose that many property changes after dimerization cannot be simply explained by the effect on the intramolecular aggregation. The origin of these property changes caused by dimerization may be the effect of dynamic photophysical properties and should be pursued.…”

“…[18][19][20][21][22][23] Results show that the interaction between the monomers (chromophores) in those dimers and aggregates can change their photophysical behaviors. But rarely are there reports on the potential value of these phenomena.…”

Fotoquímica de sistemas Areno/Olefina

“…Un compuesto bicromofórico es una molécula constituida por dos unidades moleculares diferenciables conectadas mediante un puente molecular y cuyo espectro de absorción es la superposición de los espectros de absorción de los dos cromóforos contenidos en ella. [1][2][3] El puente molecular es una unidad espaciadora que no influye sobre la estructura electrónica de los dos cromóforos, inhibiendo toda interacción intercromofórica en el estado fundamental y permitiendo que la excitación de cualquiera de los cromóforos dé lugar a interacciones entre ellos, pudiéndose observar la formación de complejos (exciplejos) o procesos intramoleculares de transferencia de electrón, de protón o de energía.…”