Structure and Properties of Dynamic Rigid Rod-Like Metallo-Supramolecular Polyelectrolytes in Solution

Abstract

Metal-ion-induced self-assembly in aqueous solution of the rigid ligand 1,4-bis(2,2 0 :6 0 ,2 00terpyridine-4 0 -yl)benzene (1) with Fe(OAc) 2 and Ni(OAc) 2 is investigated with viscosimetry, SANS, and AFM. Ligand 1 forms extended, rigid-rod like metallo-supramolecular coordination polyelectrolytes (MEPEs) with a molar mass of up to 200 000 g mol -1 under the current experimental conditions. The molar mass depends on concentration, stoichiometry, and time. By spin-coating MEPEs on a solid surface, we can image the MEPEs in real space by AFM. Both AFM and SANS confirm the extended rigid-rod-type structure of the MEPEs. As a control experiment, we also studied the flexible ligand 1,3-bis[4 0 -oxa(2,2 0 :6 0 ,2 00terpyridinyl)]propane (2). Ligand 2 does not form extended macro-assemblies but likely ringlike structures with three to four repeat units. Finally, we present a protocol to control the stoichiometry during selfassembly using conductometry, which is of paramount importance to obtain meaningful and reproducible results.

Fluorescence quenching in Zn2+-bis-terpyridine coordination polymers: a single molecule study

“…Hydrodynamic and atomic force microscopy experiments on related bis-terpyridine coordination polymers, containing transition metals like Ni 2+ , Fe 2+ , Ru 2+ or Zn 2+ , identified a linear conformation for all of these polymers. 4,16,25,47,48 Thus, these experiments are in agreement with the herein presented results and further corroborate the linear rod-like structure of the investigated Zn 2+ -bis-terpyridine coordination polymer. Fig.…”

X‐Ray Near‐Edge Absorption Study of Temperature‐Induced Low‐Spin‐to‐High‐Spin Change in Metallo‐Supramolecular Assemblies

“…[23] The ratio of metal centers to amphiphiles is adjusted by weighting in the appropriate molar masses. Herein, we investigated PACs containing two and six amphiphiles per metal ion, respectively.…”

Synthesis and Photophysical Properties of New α,Ω-Bis(Tpy)Oligothiophenes and Their Metallo-Supramolecular Polymers With Zn2+Ion Couplers

“…Ditopic conjugated oligomers with 2,2 :6 ,2 -terpyridine-4´-yl (tpy) end-groups are of interest as building blocks for the construction of electromagnetic-field-responsive MSPs (3)(4)(5)(6) with applications based on the light/electricity inter-conversion and non-linear optical phenomena (light-emitting devices, photovoltaic cells, etc.) (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21). Specific configuration of nitrogen atoms prefers tridentate facial or meridian coordination of tpy group to metal ions such as ions of Ru, Os, Ir, Fe, Zn, and Co, which gives rise to linear chains (22)(23)(24).…”