The Importance of CH···X (X = O, π) Interaction of a New Mixed Ligand Cu(II) Coordination Polymer: Structure, Hirshfeld Surface and Theoretical Studies

Non-Covalent Interactions in Polymers

Non-covalent interactions are one of the key topics in modern chemical science. These inter- and intramolecular weak interactions (e.g., hydrogen, halogen, and chalcogen bonds, stacking interactions and metallophilic contacts) have a significant effect on the properties of polymers. In this Special Issue, "Non-covalent interactions in polymers", we tried to collect fundamental and applied research manuscripts (original research articles and comprehensive review papers) focused on non-covalent interactions in polymer chemistry and related fields. The scope of the Special Issue is very broad: we welcome all the contributions that deal with the synthesis, structure, functionality and properties of polymer systems involving non-covalent interactions.

Influence of polyethylene glycol plasticizer on the structural and electronic properties of PEO-NaI complex: a density functional study

Ab initio study has been carried out to investigate the influence of low molecular weight polyethylene glycol (PEG) plasticizer on structural and electronic properties of the polyethylene oxide-sodium iodide (PEO-NaI) polymer-metal complex. DOS and PDOS analysis provided a quantitative explanation of the electronic bandgap of the PEO-NaI and PEO-PEG-NaI system. Hirshfeld population charge analysis (HPA) explains better dissociation of NaI in presence of polyethylene glycol, based on the Hard Soft Acid Base Principle. Also, an increase in amorphic content of polymer system is observed with the addition of PEG, evident from the increment in the strength of anti-bonding orbitals in COOP plot. Bond strength of the polymeric system is also found to be affected with the addition of plasticizer. The findings provide an avenue that the present polymer system [PEO-PEG-NaI] is a potential candidate to be used as an electrolyte for next-generation energy storage technology.

Solvent induced mononuclear and dinuclear mixed ligand Cu(ii) complex: structural diversity, supramolecular packing polymorphism and molecular docking studies

Phenolate bridged dinuclear and solvent induced mononuclear supramolecular isomers of Cu(ii) complex have been reported to explore the structural diversity and their antibacterial activity supported by molecular docking studies.

Solvation-Enhanced Intermolecular Charge Transfer Interaction in Organic Cocrystals: Enlarged C-C Surface Close Contact in Mixed Packing between PTZ and TCNB

The mixed π-π packing of the donor (D) and acceptor (A) molecules is the highlighting feature of the intermolecular interactions following charge transfer (CT) issues in organic cocrystal systems. There is an inverse relationship between the D-A interplanar distance and the intermolecular CT interaction. However, the D-A C-C surface close contact (relative areas) on the intermolecular CT interactions in organic cocrystal systems is rarely investigated. Herein, we designed and constructed a novel cocrystal and its solvate cocrystal. The structural and electrostatic potential analyses suggest that the solvation destroys the N-H···N hydrogen bond interaction between phenothiazine (PTZ) and 1,2,4,5-tetracyanobenzene (TCNB), which causes the TCNB molecules to have a 90° rotation along the normal axis of the PTZ plane. Thus, the D-A C-C surface close contact is enlarged, strengthening the intermolecular π-π stacking interactions and intermolecular CT interaction between PTZ and TCNB, which are further evidenced by the absorption and Raman spectroscopic analyses. This study provides rare evidence of the enlarged C-C surface close contact in the mixed packing between D and A that greatly contributes to the intermolecular CT interaction in a D-A cocrystal system. It also provides a deeper understanding of the role of solvation in the structure-property relationship of organic cocrystal materials.