Thermodynamics of complex formation equilibria between Ag(I) and thiocarbonyl ligands in propan-2-one (acetone) solution

Abstract

Complex formation equilibria in propan-2-one between Ag(I) and thiourea (Tu), thioacetamide (Ta), N-methylthiourea (MeTu), N-ethylthiourea (EtTu), N,N′-diethylthiourea (Et₂Tu), N-phenylthiourea (PhTu), N, N′-diphenylthiourea (Ph₂Tu), and thiobenzanilide (TbAn) have been investigated by potentiometry at different temperatures t = 0–20 °C and self-determined ionic medium. Formation of mono-, bis-, and tris-coordinated AgL _n complexes (charges are omitted) has been detected, but for Ag(I)–Ph₂Tu system, where the occurrence of the mono-coordinate AgPh₂Tu and bis-coordinate Ag(Ph₂Tu)₂ has been found. The stability constants have been deduced. The standard enthalpy and entropy changes have been evaluated from the linear dependence of the free energies on temperature.

Graphical abstract

Keywords:

• Silver ion complexes
• Thiourea complexes
• Enthalpy–entropy relationships
• Non-aqueous solvents
• Propan-2-one

Disclosure statement

No potential conflict of interest was reported by the author.