ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 36, Number 5
JKCSEZ 36(5)
October 20, 1992 

The effects of Ca2+ ion on the charge transfer(CT) interaction of 4-(C9H19)C6H4O(CH2CH2O)40 [NP-(EO)40] with iodine in aqueous solution were investigated by UV-visible spectrophotometer. Maximum absorption wavelengths to the CT interaction were in the vicinity of 390 nm, and by the addition of Ca2+ ion shifted toward 370 nm. Above CMC, the intensity of the CT interaction by the addition of Ca2+ ion were increased and then decreased. The increase in the intensity of CT band were attributed to the increase of the donor-acceptor overlap with iodine caused by the compactness of micelle in the presence of Ca2+ ion. These phenomena suggest that the linear oxyethylene(EO) chains, relatively free to assume various configuration in aqueous solution, could form a pseudo-crown ether structures capable of forming complexes with Ca2+ ion.