Owing to their rigid structure, MR-TADF compounds typically show much narrower emission profiles and smaller Stokes shifts while also exhibiting larger molar absorptivities for the low-energy short-range charge transfer (SRCT) absorption band (see Figure ). The emissive excited state also shows SRCT character, which is identifiable due to the modest positive solvatochromism, in contrast to the large positive solvatochromism observed for D-A TADF compounds (see Figures ). Enhanced molar absorptivity and reduced positive solvatochromism are expected to have positive implications for photocatalysis reactivity. The higher molar absorptivity of the band that is being targeted for photoexcitation could translate to faster reaction rates and lower required photocatalyst loadings. The attenuated positive solvatochromism of MR-TADF compounds implies that less energy is lost due to stabilization of the excited state by solvent, potentially leading to greater reactivity of the PC, particularly in commonly used polar aprotic solvents such as MeCN and DMF. DiKTa and its mesitylated analogue Mes3DiKTa were chosen for investigation as photocatalysts because of their similar redox potentials to those of 4CzIPN (Figure ). An additional benefit is that the raw material cost per mmol is significantly lower for DiKTa (£0.94/mmol) than for 4CzIPN (£3.26/mmol, see SI). These PCs were assessed across a diverse range of transformations including reductive quenching reactions, oxidative quenching reactions, energy transfer reactions, nickel dual catalysis and hydrogen atom transfer (HAT) dual catalysis. The result of this assessment shows that DiKTa and Mes3DiKTa are attractive alternatives to the widely used 4CzIPN.