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A one dimensional copper(II)-based perovskite, (C5H8N3)[CuCl3], was successfully synthesized. XR-diffraction demonstrates that the mineral framework of this perovskite is formed by infinite needle-like chains [CuCl3] −∝ , where each Cu2+ ion, with its [4+2] coordination sphere, adopts a nearly tetragonal symmetry. The simultaneous TGA/DSC analyses demonstrate the stability of the material at ambient temperature and up to 130 °C. The convergence of the optical experimental results and the theoretical DFT calculations of the electronic structure demonstrates the semiconducting character of the synthesized compound with an experimental direct band gap energy of 2.21 eV. The optical analysis shows that a cooperative Jahn–Teller effect is manifested around the copper ions. Both ligand to metal charge transfer (LMCT) transitions and crystal field transitions (d–d) make the material suitable for green solar cell applications. The magnetic properties of (C5H8N3)[CuCl3] can be described by a model of S = 1/2 antiferromagnetic dimers with exchange interaction J/kB = −122.7 K. [ABSTRACT FROM AUTHOR]

A mononuclear cobalt(ii) complex [C 5 H 8 N 3 ] 2 [CoCl 4 (C 5 H 7 N 3 ) 2 ] (I) was synthesized and structurally characterized. Single crystal X-ray diffraction analysis indicates that monometallic Co(ii) ions acted as coordination nodes in a distorted octahedral geometry, giving rise to a supramolecular architecture. The latter is made up of a ½ unit form composed of an anionic element [Co 0.5 Cl 2 (C 5 H 7 N 3 )] - and one 2-amino-4-methylpyrimidinium cation [C 5 H 8 N 3 ] + . The crystalline arrangement of this compound adopts the sandwich form where inorganic parts are sandwiched between the organic sheets following the [100] direction. More information regarding the structure hierarchy has been supplied based on Hirshfeld surface analysis; the X⋯H (X = N, Cl) interactions play a crucial role in stabilizing the self-assembly process of I, complemented by the intervention of π⋯π electrostatic interaction created between organic entities. Thermal analyses were carried out to study the thermal behavior process. Static magnetic measurements and ab initio calculations of compound I revealed the easy-axis anisotropy character of the central Co(ii) ion. Two-channel field-induced slow-magnetic relaxation was observed; the high-frequency channel is characterized by underbarrier relaxation with U eff = 16.5 cm -1 , and the low-frequency channel involves a direct relaxation process affected by the phonon-bottleneck effect., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Detailed structural information is essential for understanding the properties of TCNQ and TCNQF 4 compounds (TCNQ = 7,7,8,8-tetracyanoquinodimethane; TCNQF 4 = 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane). The ineludible requirement of obtaining crystals of a size and quality sufficient to yield a successful X-ray diffraction analysis has been challenging to satisfy because of the instability of many of these compounds in solution. Crystals of two new complexes of TCNQ, [ trans -M(2 ampy ) 2 (TCNQ) 2 ] [M = Ni ( 1 ), Zn ( 2 ); 2ampy = 2-aminomethylpyridine], as well as unstable [Li 2 (TCNQF 4 )(CH 3 CN) 4 ]·CH 3 CN ( 3 ), can be prepared in minutes by a horizontal diffusion technique and can be harvested easily for X-ray structural studies. Compound 3 , previously described as "Li 2 TCNQF 4 ," forms a one-dimensional (1D) ribbon. Compounds 1 and 2 can also be obtained as microcrystalline solids from methanolic solutions of MCl 2 /LiTCNQ/2 ampy . Their variable-temperature magnetic studies confirmed a contribution of strongly antiferromagnetically coupled pairs of TCNQ •- anion radicals at higher temperatures with exchange coupling J / k B = -1206 K and J / k B = -1369 K for 1 and 2 , respectively, estimated using a spin dimer model. The presence of magnetically active anisotropic Ni(II) atoms with S = 1 in 1 was confirmed, and the magnetic behavior of 1 , representing an infinite chain of alternating S = 1 sites and S = 1/2 dimers, was described by a spin-ring model suggesting ferromagnetic exchange coupling between Ni(II) sites and anion radicals., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)