The complex also indicates 40% LS-to-HS conversion after photoirradiation with green light (λ= 532 nm) at 2 K, reaching a maximum value of 2.58 cm temperature fluorescence emission spectra were recorded for complex 6 and 6-d in the temperature range of 80-300 K to study the synergistic correlation of SCO and luminescence. The optimum excitation wavelength came to be 375 nm for 6-d. Upon excitation, a broad emission band came in the 370 to 700 nm range, with the maximum emission at 420 nm. The band is attributed to the π-π * transition of the pybox moiety from the ligand backbone. The emission intensity continuously increases by lowering the temperature to 5 K due to the restriction of non-radiative transition processes at the low temperature (Fig. ).