roshanak rostamian - department of chemistry razi university kermanshah
mohsen irandoust - department of chemistry razi university kermanshah

proton NMR spectroscopy was used to study of complexation reaction of Li+ with 15-crown-5 15C5 in a number of binary acetonitril AN , nitrobenzene NB mixtures at different temperatures in all cases the exchange between free and complexed 15C5 was fast on the NMR time scale and only a single population average H signalwas observed.

15-crown -5,Li+,proton NMR , mixed solvent ,stoichiometry, formation constant , enthalpy , entropy