Experimental and Computational Study of Counterintuitive ClO₄^–···ClO₄^– Interactions and the Interplay between π⁺–π and Anion···π⁺ Interactions

Abstract

The novel non-covalent interactions between the charged and neutral aromatic rings and with anions are utilized to design the solid-state assembly of triply protonated PTPH 3 (PTP = 4'-(4-pyridyl)-3,2':6',3''-terpyridine) with H 2 O and three ClO 4 -, which is synthesized and characterized by single crystal X-ray diffraction analysis. Crystallography reveals that the π + -π + , π + -π and various anion···π interactions are the major driving forces in the stabilization of the selfassembled structure. In the title complex, a layered assembly is formed through the mutual influence of π + -π + and π + -π interactions. The anions are interacting with the charged π-acceptors which are again stabilized through π + -π interactions. So, the overall stabilization is governed through π + -π/π-π + , (π + -π + ) n and anion···π + /π + -π/π-π + networks in the solid state. The interaction energies of the main driving forces observed in the crystal structure have been calculated using density functional theory. In addition, the short O···O contact between ClO 4 -, anions has been analyzed in detail both computationally and exploring the Cambridge Structural Database.

Construction of Supramolecular Assemblies Based on Anion–π Interactions

“…The same group extended their study to a similar ligand, that is, the triply protonated 4′-(4-pyridyl)-3,2′:6′,3″-terpyr idine) molecule and perchlorate as counterion [109]. Crystallography reveals that π + -π + , π + -π, and various anion-π interactions are the major driving forces in stabilization of the several assemblies observed in the solid-state structure.…”

Influence of anions and solvent molecules on the packing and emission spectra of coordination polymers based on silver ions and an anthracene derivative

“…7a). Consequently, each triflate ion strongly immobilizes a pair of parallel chains, which results in the maximization of the face-toface π-π interactions 15 between the anthracene planes (Ag-O, ca. 2.67 Å).…”

Structural diversity in mercury(II) coordination complexes with asymmetrical hydrazone-based ligands derived from pyridine

“…Over the last few years bis(pyridyl)-2,3-diaza-1,3-butadiene has become a well-known ligating linker in coordination chemistry. In modern design of coordination architecture the role of all possible noncovalent interactions in self-assembly and supramolecular recognition have to be considered along with strong and weaker hydrogen bonds such as N-H…O/N [23][24], N-H…halogen [25], as well as the π…π interactions [26][27][28][29][30]. Furthermore, the presence of additional substituents in the central aliphatic linker, as well as the position of N atoms in the pyridyl rings, had significant influence on the resulting assembly of the coordination framework.…”