Solution thermodynamics of iron(III)-N,N′-ethylene-bis(salicylideneiminato)-chloride in binary mixtures of N,N-dimethylformamide and acetonitrile at T = (298.15, 303.15, 308.15 and 313.15) K

• Binary mixture of N,N-dimethylformamide and acetonitrile used as solvent.
• Iron(III)-N, N′-ethylenebis(salicylideneiminato)chloride was used as solute.
• Limiting apparent molar volumes and viscosity B-coefficients of the solute were determined.
• The sign of (∂ϕE0/∂T)P values were indicated the structure promoting ability of the solute.
• Strong (solute + solvent) interactions are present in the ternary systems studied.

Limiting apparent molar volumes (ϕV0) and viscosity B-coefficients of iron(III)-N, N′-ethylene-bis(salicylideneiminato)-chloride in binary mixtures of N, N-dimethylformamide (DMF) + acetonitrile (ACN) were determined from solution density and viscosity measurements at T = (298.15, 303.15, 308.15 and 313.15) K under ambient pressure. In the investigated temperature range, the relation: ϕV0=a0+a1T+a2T2, was used to determine the temperature dependence of the ϕV0 values (∂ϕV0/∂T)P,i.e.  , partial molar expansibilities (ϕE0). The temperature dependence of partial molar expansibilities (ϕE0), i.e.,  (∂ϕE0/∂T)P and viscosity B-coefficients were used to reveal the nature and degree of (solute + solvent) and (solvent + solvent) interactions in the ternary solutions. The transition state theory was applied to analyze the viscosity B-coefficients on the basis of the activation parameters of viscous flow. The results indicated strong (solute + solvent) interactions between FeIII(salen)Cl and the solvent mixtures. FeIII(salen)Cl was found to be a structure promoter in the ternary solutions.

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