Synthesis, crystal structure, vibrational study, optical properties and thermal behavior of a new hybrid material bis(3-amino-4-phenyl-1H-pyrazolium) tetrachloridocobaltate (II) monohydrate

A Nickel-Based Semiconductor Hybrid Material with Significant Dielectric Constant for Electronic Capacitors

A novel semiconducting Ni(II)-based hybrid material with the formula (C7H12N2) NiCl4, which exhibits interesting optical and electrical properties, is reported. The crystal structure was investigated using SCXRD, whereas physical properties were studied by means of thermal analysis, Ft-Infrared, optical, and electrical measurements. Its crystal packing is formed through organic rings surrounded by inorganic [NiCl4]2- tetrahedral and stacked along the a-crystallographic axis. This arrangement is stabilized by a dense network of intermolecular hydrogen bonds. The investigated compound displayed a wide absorption range across the visible spectrum, characterized by an optical gap energy of 2.64 eV, indicating its semiconducting nature and efficient sunlight absorption capabilities across various wavelengths. Such features are of utmost importance in achieving a high energy conversion efficiency in solar cell applications. Further analyses of the thermal behavior using differential scanning calorimetry revealed a single-phase transition occurring at around 413 K, which was further confirmed through electrical measurements. A deep investigation of the electric and dielectric performances demonstrated a significant dielectric constant (ε' ∼ 104) at low frequencies and low dielectric loss at high frequencies. Thus, it highlights its exceptional dielectric potential, particularly in applications related to electronic capacitors.

Stabilization of Tetrachloride with Mn (II) and Co (II)Complexes and 4-Tert-Butylpyridinium Organic Cation: Elaboration of the Structure and Hirshfeld Surface, Optical, Spectroscopic and Thermal Analyses

[C9H14N]2[MnCl4] (I) and [C9H14N]2[CoCl4] (II) are isostructural compounds produced via gradual evaporation at room temperature. Both compounds consolidate in the tetragonal space group I4¯2d (No. 122), as shown by single-crystal X-ray diffraction observations. A slightly deformed tetrahedral geometry is formed by four chloride atoms around each cation MII (M = Mn or Co). The [C9H14N]+ groups and the isolated [MCl4]2− units are connected via C–H…Cl and N–H…Cl H-bonds to form sheets parallel to the (101¯), (011), (01¯1) and (101) planes. The morphology and the chemical composition of compounds (I) and (II)were determined here using SEM and EDX. The functional groups contained in both compounds were determined using FT-IR spectroscopy. The study of the optical characteristics showed that the two compounds exhibited semiconductor behavior. The thermal analysis (TGA-DTA) was used to determine their thermal stability.