Initially, the complexes 1-3 showed a lower energy absorption band at 392 nm in 100% DMF. The slow increase of water content to DMF from 0% to 70% lead to the reduction in absorption coefficient of absorption band at 392 nm in all complexes. Additionally, the slope of the lower energy absorption band shows a slight shift towards lower energy as shown in figure . This shift may be attributed to the enhanced - interaction of the ligands and the inorganic part of the complexes and increases with the size and -donation ability of the ancillary ligand increases. The addition of water from 70% to 99% to DMF caused the aggregation of molecules which lead to a further broadening of the absorption band along with observation of long tail due to the scattering with the aggregates. Interestingly, at 99% water added, a reduction in absorption intensity, as well as a blue shift (1: 392 to 380 nm; 2: 392 to 382 nm) was observed for the lower energy absorption band. Moreover, the reduction in the absorption intensity confirmed the reduced oscillator strength of in 1 and 2. In contrast, the addition of 99% water to 3 showed the red shift and broadening of the absorption band along with the enhancement of absorption intensity which suggests an enhanced oscillator strength because of aggregation in complex 3 (Figure ). The photoluminescence spectra of all complexes 1-3 were also recorded with increasing water content (0 to 99%) in DMF. As shown in figure , in 100% DMF all complexes emit at ~468 nm suggesting that similar excited states are responsible for the emission. Increasing the water content to DMF from 0 to 70% red shifts all emission bands from 468 to 480 nm. Alongside, a reduction in the emission intensity was observed with the increasing water content which suggest that aggregation caused quenching (ACQ), as well as other non-radiative pathways are responsible for the reduction in emission intensity.