Remarkable near-infrared chiroptical properties of chiral Yb, Tm and Er complexes

We carried out a study of absorption (CD) and emission (CPL) chiroptical properties in the NIR region of two sets of Yb, Tm and Er complexes. The two complexes include a D-3 symmetric, [TMG-H+](3)Ln(BINOLate)(3) (Ln = Yb, Tm, Er; TMG = 1,1,3,3-tetramethylguanidine; BINOLate = 1,1 '-bi-2-naphtholate), and a tetrakis, C-4 symmetric, CsLn(hfbc)(4) (Ln = Yb, Tm, Er; hfbc = 3-heptafluorobutylyrylcamphorate). The lanthanides studied gave access to three discrete energy domains, Yb (900-1040 nm), Tm (1180-1240 nm) and Er (1430-1600 nm) in which the chiroptical activity was assessed using g(abs) (and g(lum) for Yb complexes). Exceptionally high discrimination between left and right circularly polarised light was observed, with values up to almost the theoretical maximum (+/- 2).

Automated summary

The study investigated absorption (CD) and emission (CPL) chiroptical properties in the NIR region of two sets of Yb, Tm, and Er complexes, showing exceptionally high discrimination between left and right circularly polarized light. Lanthanides provided access to three discrete energy domains, with values reaching almost the theoretical maximum.