Triphenylmethane leucoderivatives

The fourth mechanism (4) invokes the electrostatic repulsion between photogenerated charges as the driving force for conformation changes. Triphenylmethane leucoderivatives (72) have been used as photoreceptor molecules. The chromophore dissociates into an ion-pair under ultraviolet irradiation, generating an intensely green colored triphenylmethyl cation. The cation thermally recombines the counter anion as follows. 

The transport property of poly(L-glutamic acid) membrane 24) was also photo-controlled by incorporating triphenylmethane leucoderivative, pararosaniline, groups [60]. The pararosaniline groups in the membrane dissociate into ion-pairs upon ultraviolet irradiation, yielding hydroxide ions. 

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