Solubility measurements and thermodynamic correlation of bis(imino)pyridine-based Cu and Ni complexes in pure solvents

IF 5.3 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Liquids Pub Date : 2025-03-01 DOI:10.1016/j.molliq.2025.127268

Talha Baig , Ziyuan Pang , Mubashar Ilyas , Muhammad Abbas , Sheza Tahir , Xiaoli Ma

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引用次数: 0

Abstract

In this work, the solubility of a bis(imino)pyridine-based ligand L = 2,6-Bis[1-(cyclohexylimino)ethyl]pyridine and its two metal complexes LCuCl₂ and LNiCl₂ is measured by static equilibrium method in four selected solvents. These complexes are widely used in catalysis, polymerization, cycloaddition reactions, anticancer drugs, and in optoelectronic materials where the solvation process has a critical impact on their properties. The solubility data is vital for improving the crystallization process and the efficiency of homogeneous catalysis. Six thermodynamic models (Apelblat, Polynomial, Yaws, Vant’s Hoff, λh, and NRTL) are applied to analyze the solubility values of LH and four models (Apelblat, Polynomial, Yaws, Vant’s Hoff) are applied for both metal complexes LCuCl₂ and LNiCl₂. To ensure the precision of experimental data, the ARD and RMSD values are calculated for accuracy evaluation. The solubility data of L indicates that dichloromethane is the best reaction solvent having its highest solubility value 7.515 × 10² x at 298.15 K and absolute ethanol is the best solvent for its crystallization. Similarly, the solubility data collected for LCuCl₂ and LNiCl₂ reveals that trichloromethane is the best reaction solvent having highest solubility values 4.188 × 10³ x and 4.279 × 10³ x respectively at 298.15 K and acetone is the crystallization solvent for both of these metal complexes. The polynomial model represents the optimal choice for accurately fitting the solubility data related to all three examined compounds having average ARD values less than 1 %. Hirshfeld surface analysis show that H⋯H contacts are the most significant interactions, about 68.2 % in the compound LCuCl₂. Moreover, molecular electrostatic potential indicates that the N atom and the metal centers of the two compounds exhibit distinct electronegativity. In addition, functions related to apparent thermodynamics were obtained. The dissolution process proved endothermic and entropy rose in the experimental settings, with spontaneous energy accounting for the variation in solubility.

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来源期刊

Journal of Molecular Liquids 化学-物理：原子、分子和化学物理

CiteScore

10.30

自引率

16.70%

发文量

2597

审稿时长

78 days

期刊介绍： The journal includes papers in the following areas: – Simple organic liquids and mixtures – Ionic liquids – Surfactant solutions (including micelles and vesicles) and liquid interfaces – Colloidal solutions and nanoparticles – Thermotropic and lyotropic liquid crystals – Ferrofluids – Water, aqueous solutions and other hydrogen-bonded liquids – Lubricants, polymer solutions and melts – Molten metals and salts – Phase transitions and critical phenomena in liquids and confined fluids – Self assembly in complex liquids.– Biomolecules in solution The emphasis is on the molecular (or microscopic) understanding of particular liquids or liquid systems, especially concerning structure, dynamics and intermolecular forces. The experimental techniques used may include: – Conventional spectroscopy (mid-IR and far-IR, Raman, NMR, etc.) – Non-linear optics and time resolved spectroscopy (psec, fsec, asec, ISRS, etc.) – Light scattering (Rayleigh, Brillouin, PCS, etc.) – Dielectric relaxation – X-ray and neutron scattering and diffraction. Experimental studies, computer simulations (MD or MC) and analytical theory will be considered for publication; papers just reporting experimental results that do not contribute to the understanding of the fundamentals of molecular and ionic liquids will not be accepted. Only papers of a non-routine nature and advancing the field will be considered for publication.