Selective determination of Sm (III) in lanthanide mixtures by thermal lens microscopy

Since lanthanides are inner transitional elements with their 4f and 5d energy levels closed, they possess narrow electronic absorption peaks, which are little affected by their chemical environment. In this research, a thermal lens microscope (TLM) that utilizing diode lasers as pump and probe beams was constructed for selective determination of Sm (III) without any pre-concentration and separation procedure. The calibration plot has a linear behavior over the 0.5–500 μg mL−1 range and a limit of detection (LOD) of 0.08 μg mL−1. The relative standard deviation (RSD) is smaller than 5%. This method can be potentially applicable to environmental studies.