Spectrophotometric investigation of the complex formation between aza-15-crown-5 containing chromoionophores and alkali and alkaline earth metal ions in acetonitrile.

Complexation of two cationic styryl dyes containing aza-15-crown-5 moiety and Na(+), K(+), Ca(2+) and Ba(2+) was investigated spectrophotometrically in water-containing acetonitrile medium. The ligand/complex ratio was estimated using a method for resolution of overlapping bands. A model for evaluation of the water action is proposed and stability constants were calculated for all metal ions in question.