Synthesis, structures, thermal and magnetic properties of two bis(oxalato)cuprate(II) hybrid salts containing pyridinium derivative cations

A New Cu(II) Metal Complex Template with 4–Tert–Butyl-Pyridinium Organic Cation: Synthesis, Structure, Hirshfeld Surface, Characterizations and Antibacterial Activity

In this paper, we report on the chemical preparation, crystal details, vibrational, optical, and thermal behavior, and antibacterial activity of a new non-centrosymmetric compound: 4-ter-butyl-pyridinium tetrachloridocuprate. X-ray diffraction analysis shows that the structure has a 3Dnetwork made up of C–H…Cl and N–H…Cl H-bonds, and [CuCl4]2− anions have a shape halfway between a tetrahedron and a square planar structure in this compound’s monoclinic system. Hirshfeld surface analysis was used to explain the nature and extent of intermolecular interactions, highlighting the importance of the H-bonds and the C–H⋯π interactions in the structure’s stabilization. Additionally, SEM/EDX experiments were conducted. The powder X-ray diffraction investigation at room temperature validated the material purity. Moreover, the different functional groups were identified using FT-IR spectroscopy. In addition, the optical properties were investigated using UV-Vis absorption. The thermal stability of (C9H14N)2[CuCl4] was performed by TGA-DTA. The bactericidal potency of the title compound was surveyed.

Sorption and Magnetic Properties of Oxalato-Based Trimetallic Open Framework Stabilized by Charge-Assisted Hydrogen Bonds

We report a new structure of {[Co(bpy)₂(ox)][{Cu₂(bpy)₂(ox)}Fe(ox)₃]}_n·8.5nH₂O NCU-1 presenting a rare ladder topology among oxalate-based coordination polymers with anionic chains composed of alternately arranged [Cu₂(bpy)₂(ox)]²⁺ and [Fe(ox)₃]³⁻ moieties. Along the a axis, they are separated by Co(III) units to give porous material with voids of 963.7 ų (16.9% of cell volume). The stability of this structure is assured by a network of stacking interactions and charge-assisted C-H…O hydrogen bonds formed between adjacent chains, adjacent cobalt(III) units, and alternately arranged cobalt(III) and chain motifs. The soaking experiment with acetonitrile and bromobenzene showed that water molecules (8.5 water molecules dispersed over 15 positions) are bonded tightly, despite partial occupancy. Water adsorption experiments are described by a D’arcy and Watt model being the sum of Langmuir and Dubinin–Serpinski isotherms. The amount of primary adsorption sites calculated from this model is equal 8.2 mol H₂O/mol, being very close to the value obtained from the XRD experiments and indicates that water was adsorbed mainly on the primary sites. The antiferromagnetic properties could be only approximately described with the simple Cu^II-ox-Cu^II dimer using H = −J·S₁·S₂, thus, considering non-trivial topology of the whole Cu-Fe chain, we developed our own general approach, based on the semiclassical model (SC) and molecular field (MF) model, to describe precisely the magnetic superexchange interactions in NCU-1. We established that Cu(II)-Cu(II) coupling dominates over multiple Cu(II)-Fe(III) interactions, with J_CuCu = −275(29) and J_CuFe = −3.8(1.6) cm⁻¹ and discussed the obtained values against the literature data.

One-dimensional magnetism in a facile spin 1/2 Heisenberg antiferromagnet with a low saturation field

This work reports the synthesis, structure and magnetic properties of the single crystal of a facile spin 1/2 one dimensional Heisenberg antiferromagnet bis(4-aminopyridinium) bis(oxalato)cuprate(II) dihydrate, (C5H7N2)2[Cu(C2O4)2].2H2O. Single crystals of large...