Aligned 1-D Nanorods of a π-Gelator Exhibit Molecular Orientation and Excitation Energy Transport Different from Entangled Fiber Networks

Abstract

Linear π-gelators self-assemble into entangled fibers in which the molecules are arranged perpendicular to the fiber long axis. However, orientation of gelator molecules in a direction parallel to the long axes of the one-dimensional (1-D) structures remains challenging. Herein we demonstrate that, at the air-water interface, an oligo(p-phenylenevinylene)-derived π-gelator forms aligned nanorods of 340 ± 120 nm length and 34 ± 5 nm width, in which the gelator molecules are reoriented parallel to the long axis of the rods. The orientation change of the molecules results in distinct excited-state properties upon local photoexcitation, as evidenced by near-field scanning optical microscopy. A detailed understanding of the mechanism by which excitation energy migrates through these 1-D molecular assemblies might help in the design of supramolecular structures with improved charge-transport properties.

Nanosheets of an Organic Molecular Assembly from Aqueous Medium Exhibit High Solid‐State Emission and Anisotropic Charge‐Carrier Mobility

“…[47] The solution state LD measurements of PDPP-Amphi in water (c = 3 × 10 -4 m) exhibited significant negative LD signal indicating greater perpendicular (A ⊥ ) absorption of the polarized light than parallel (A ∥ ) due to perpendicular orientation of the transition dipole moment with respect to the sheet direction. [49] Density functional theory (DFT) calculations have been performed to know more about the molecular conformation and the frontier molecular orbitals (FMOs). [49] Density functional theory (DFT) calculations have been performed to know more about the molecular conformation and the frontier molecular orbitals (FMOs).…”

Theoretical studies of molecular orientation and charge recombination in poly-paraphenylenevinylene light-emitting diodes

“…For example, orientation and organization of p-phenylenevinylene derivatives have been paid much attention. 45 In some cases, orientation and arrangements of the component chromophores are highly controlled and modified. It is noted that the methyl-substituted system, OPV3-methyl, has a larger value in the charge recombination factor than the nonsubstituted OPV3 as shown in Table 2.…”

Molecular aggregation of naphthalimide organic semiconductors assisted by amphiphilic and lipophilic interactions: a joint theoretical and experimental study

“…Note that tuning the molecular packing in organic semiconductors normally has tremendous influence on the electronic properties. [29][30][31] Our molecular design consists of naphthalimide-fused thienopyrazine (NIP) derivatives NIP-3T Amphi and NIP-3T Lipo with A-D units. The donor moiety consists of terthiophene units connected by a pyrazine linker to the naphthalimide.…”