Revealing the impact of the rotational isomerism onto photoluminescent properties of some ortho derivatives of benzophenone

• A group of ortho -benzophenone derivatives is subjected to a conformational analysis. • For certain o -BP compounds, two alternative conformations are identified to be stable. • Existence of two distinct conformers, syn and anti, is evaluated spectroscopically. • The unveiled isomers are observed to exhibit different luminescent properties. Benzophenone (BP) scaffold, owing to its highly applicable photo-related properties, has been widespread among many branches of chemical research and industry. While the benzophenone molecule itself has been extensively studied towards the intrinsic mechanisms standing behind its prominent nature, yet its derivatives still tend to be under-explored in this particular regard. Coming across the disclosed imparity, throughout the present paper, a subject of rotational isomerism, anticipated to affect the BP frameworks substituted in the ortho position, is thoroughly investigated. In this respect, a bunch of ortho derivatives of BP are subjected to a systematic analysis carried out via both in silico DFT modeling and spectroscopic measurements (IR, UV–Vis). The obtained results show that the effect of rotamerism indeed applies to the studied group of compounds, as some of them reveal themselves in the form of multiple coexisting conformational isomers. What is more, as the indicated conformers are found to be characterized by substantially different emission profiles, the foregoing phenomenon is disclosed to have quite a remarkable impact onto the photoluminescence of the explored o -BP molecules.