A combined experimental and density functional theory study on the complexation ability of 15-crown-5 with Li+, Na+, K+, and NH4 (+) cations

作者：Rounaghi Gholam Hossein^*; Razavipanah Iman; Deiminiat Behjat; Razghandi Fahimeh; Koohsarian Esmat; Abedinzadeh Najmeh

来源：Journal of the Iranian Chemical Society, 2014, 11(3): 599-606.

DOI：10.1007/s13738-013-0329-y

• Complexation process
• Conductometry
• DFT study
• Liquid phase
• Gas phase

The complexation processes among Li+, Na+, K+, and NH4 (+) cations with the macrocyclic ligand, 15-crown-5 (15C5) have been studied in acetonitrile-methanol binary mixtures at different temperatures using conductometric method. The stability constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductance-mole ratio data at various temperatures. The values of thermodynamic parameters ( and ) for the formation of the complexes were obtained from temperature dependence of the stability constants of complexes using van't Hoff plots. In addition, a theoretical study has been carried out using density functional theory to obtain the stability of the complexes and the geometrical structure of the 15C5 and its complexes with Li+, Na+, K+ and NH4 (+) cations in the gas phase. We compared the experimental data with those obtained by quantum chemistry calculations to investigate the effect of the solvent on complexation process.

• 出版日期2014-6