The simple modification of the hydroxypropyl arm in Gd(HP-DO3A) complex allows to achieve an increased relaxivity by activation intramolecular catalysis proton exchange process.

Homoleptic tetra-coordinated copper(i)-chalcogenone complexes have been reported with rare proximity-enforced intramolecular Cu⋯H–C(sp3) hydrogen bonding interactions.

Utilizing the intramolecular CH–N hydrogen bonding and bulky substituents at reactive carbons resulted in development of photochromic diarylbenzene with both high photoreactivity fast thermal back reactivity.

The protonation of carbazole derivatives results in the restriction intramolecular rotation, planarization molecule and relocalisation LUMO orbital increasing fluorescence quantum yield from 16% to 80%.

The mechanofluorochromism is related to the optical properties according electron push–pull substituent effect. As intramolecular charge transfer decreases, strong intermolecular interactions occur, leading mechanofluorochromism.