The invention relates to the use of compounds comprising at least one 2-(1H-tetrazol-5-yl)pyridine unit, of formula (I) below: as ligands for lanthanides and, more especially, as organic chromophores for complexing these elements. It also relates to lanthanide complexes using these compounds as complexing organic chromophores, and to new compounds containing one or more 2-(1H-tetrazol-5-yl)pyridine units, which are useful as ligands for lanthanides and, in particular, as organic chromophores for complexing these elements.Applications: photonics and optoelectronics, especially for forming light-emitting devices such as electroluminescent diodes; biology, as for example for the preparation of luminescent probes.