The new emissive complex, Zn(bqdi)(H2O2)(2)(2+), was synthesized, and its photophysical properties were investigated. Zn(bqdi)(H2O)(2)(2+) emits strongly in the visible region at pH = 8.0, but the intensity decreases by a factor of 8 at pH = 3.0. The ability of the complex to "turn on" its emission as a function of pH may prove useful in switching or sensing applications.