Thermodynamics studies of fluorescence quenching and complexation behavior of thallium(I) ion with some polyazamacrocycles

摘要: Abstract The mechanism of fluorescence quenching and stability the complex formation thallium(I) ion with polyazamacrocycles [12]aneN3, Me3[12]aneN3, [12]aneN4, [14]aneN4, [18]aneN6 Me6[18]aneN6 were studied in methanol solution at different temperatures spectrofluoromertrically. factors affecting complexation behavior found as size polyazamacrocycle substitution methyl groups on nitrogen atoms macrocyclic ring. All ligands form a 1:1 2.5 × 10−5 M concentration 15, 20, 25 30 °C. Linear Stern–Volmer plots obtained for Me3[12]aneN3 [14]aneN4 (first group). In contrast, cases systems (second group) an upward curvature was observed corresponding plots. From temperature dependence quenching, it is demonstrated that process probably static first group. However, case second group, both dynamic mechanisms contribute to thallium fluorescence. constants thermodynamic parameters ΔH°, ΔS° ΔG° have been determined influence number members macrocycle ring complexes discussed. A green emission Tl+-Me6[18]aneN6 room temperature.