A quantitative structure-activity relationship (QSAR) study was performed on 20 dyes. The structural parameters, Kow ( distribution coefficient between octanol and water), EHOMO (energy of highest occupied molecular orbital) and ELUMO (energy of lowest unoccupied molecular orbital) for the dyes were estimated using commercial software packages the first order removal rate constant (k), as the activity parameter, was estimated from the experimental data of the respective photodegradation run. The QSAR model for the dyes established by ...