A spectrophotometric study of the charge transfer complexes of [60]fullerene with different tert-butylcalix[4]crowns

Abstract Formation of the charge-transfer complexes between various calix[4]crowns ( 1 – 4 ) and [60]fullerene were studied in toluene solution using UV–vis spectrophotometry. The stability constants and the thermodynamic data of the resulting 1:1 complexes were determined and were found to decrease with increasing the size of the crown moiety of the calixcrown. Except the complex of 3 , all the complexes were found to be enthalpy stabilized but disfavored in terms of entropy.