New luminescent lanthanide-based coordination compounds: Synthesis, studies of optical properties and application as marker for gunshot residues

New lanthanide-based luminescent coordination compounds containing thiabendazole (TBZ) as ligand were synthesized. Elemental analysis, mass spectrometry, thermogravimetric analysis and infrared spectroscopy were important for structural elucidation, providing the following chemical structures: [Eu(TBZ)(2)(NO3)(3)]center dot H2O and [Tb(TBZ)(2)(NO3)(3)]center dot H2O, called as EuTBZ and TbTBZ, respectively. Photoluminescence spectroscopy was also performed. EuTBZ and TbTBZ emitted characteristic red (618 nm) and green (542 nm) light, corresponding to chromaticity coordinates (0.57; 0.40) and (0.23; 0.54), respectively. Emission quantum efficiency of EuTBZ D-5(0) was 57%. TbTBZ showed higher quantum yield than EuTBZ, 35% against 0.2%. Forensic tests were performed using TbTBZ as a marker in the 9mm ammunition allowing visualizing luminescent gunshot residues (GSR) on the target, weapon and cartridge. It can help experts in analyzing crime scene, directing GSR collection and providing an optical and chemical signature to GSR derived from non-toxic ammunition.