A supramolecular structure with an alternating arrangement of donors and acceptors constructed by a trans-di-C60-substituted Zn porphyrin derivative in the solid state

Abstract

When a molecule is constructed from geometrically isotropic [such as [60]fullerene (C 60 )] and anisotropic (such as porphyrin) units, as in the case of a trans-di-C 60 -substituted Zn porphyrin derivative (diZnCPD), great interest lies in the understanding of their individual contributions to structural formations and phase transitions. For this purpose, the compound, diZnCPD, was designed and synthesized. Its phase behavior was investigated via differential scanning calorimetry (DSC) and polarized light optical microscopy (POM) and its supramolecular structure was elucidated via wideangle X-ray diffraction (WAXD) and selective area electron diffraction (SAED) in transmission electron microscopy (TEM). The diZnCPD possesses a polymorphism in its ordered structures. When cooled from the isotropic (I) phase with experimentally accessible rates, instead of transferring into its ultimate stable phase, this compound formed a less ordered, metastable phase with a layered structure at 152 C. Annealing this metastable phase enabled a further transformation into a stable phase with a higher transition temperature. As such, this metastable phase is monotropic. The formation of the stable phase was thus thermodynamically favorable, but kinetically more difficult (with a higher barrier for the transformation). Direct formation of this stable phase from the I state was unsuccessful even after prolonged isothermal experiments over several days above 152 C, indicating that the formation barrier of this stable phase is extremely high. The thermally stable phase possessed a supramolecular structure with a triclinic unit cell of a ¼ 3.34 nm, b ¼ 2.01 nm, c ¼ 1.88 nm, a ¼ 89 , b ¼ 98 , and g ¼ 90 . Detailed structural analysis revealed that this is a donor-acceptor separated structure of C 60 s and porphyrins nearly along the [01 1] direction within which the zig-zag shaped C 60 channels are along the [001] direction of the unit cell. We believe this is the first example of generating a donor-acceptor separated structure of C 60 s and porphyrins in the bulk through a thermal annealing process. This structure provides promising potential for the use of this material to fabricate supramolecular electronic devices without utilizing a solvent process. À _ and porphyrin + _) from photo-excited species. [40][41][42][43][44] Among all the structures, face-to-face aligned C 60 -porphyrin dyads

Design, Synthesis, and Self‐Assembly Behavior of Liquid‐Crystalline Bis‐[60]Fullerodendrimers

“…The above‐mentioned fullerene derivatives gave rise to nematic, smectic, columnar, and cubic phases. With the exception of a bis‐[60]fullerene–porphyrin material, for which a triclinic unit cell was obtained, all [60]fullerene‐containing liquid crystals reported so far contain only one C 60 unit. This is because the incorporation of two (or more) C 60 units within mesomorphic architectures is a difficult synthetic task that requires perfect control of the molecular design for mesomorphism to develop .…”

A Supramolecular “Double‐Cable” Structure with a 12944 Helix in a Columnar Porphyrin‐C60 Dyad and its Application in Polymer Solar Cells

“…This less‐hindered structure allows the C 60 segments to interact with each other in forming parallel C 60 inter‐column channels with stacked porphyrin columns. Furthermore, a trans ‐di‐C 60 ‐substituted Zn(II) porphryin derivative also demonstrated a supramolecular structure with an alternating arrangement of donors and acceptors in a triclinic unit cell 28, 29…”

Phase behaviour and Janus hierarchical supramolecular structures based on asymmetric tapered bisamide

“…Recently, we reported our effort toward self-assembled, hierarchical supramolecular structures in the bulk through the design and synthesis of polyhedral oligomeric silsesquioxane (POSS), [60]fullerene (C 60 ), and porphyrin based molecular Janus particles. [38][39][40] These dumbbell shaped Janus particles were effectively synthesized by thiol-ene click chemistry and their hierarchical architectures consisting of bilayered structures further organized into 3D orthorhombic lattice within layers were reported.…”