Current time in Korea 22:44 Aug 11 (Tue) Year 2020 KCS KCS Publications
KCS Publications
My Journal  Log In  Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 19, Number 6
BKCSDE 19(6)
June 20, 1998 

The Spectroscopic Studies on the Aggregation Behavior of Cyanine Dyes
Hyungsik Min, Jeunghee Park, Jongwan Yu, Dongho Kim
Aggregations of 1,1'-diethyl-2,2'-carbocyanine iodide (DCI) and 1,1'-diethyl-2,2'-dicarbocyanine iodide (DDT) in aqueous solution have been investigated by the steady-state absorption spectroscopy. The equilibrium constants for dimerization of DCI and DDT are found to be (9.8 0.5) x 104 and (1.6 0.5) x 105 M-1, respectively, at 293 K. The enthalpy changes for the dimerization of DCI and DDT are -6.7 0.7 and -7.7 0.8 kcal/mol, respectively. The results show that the dispersion force plays an important role in the aggregation of DCI and DDT in aqueous solution. The absorption bandwidth of DCI/ethanol system has been measured as a function of temperature, providing the evidence for no strong interaction between DCI and solvent molecules. The participation of hydrophobic force in driving the aggregation is suggested. For the first time, DCI in aqueous solution is found to form a new aggregate which has both J- and H- bands.
650 - 654
Full Text