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A new chiral diketonate ligand based on carvone binds early lanthanides. The Eu complex displays high circularly polarized (g(lum) = 0.82) red luminescence under near-UV excitation in the solid state. This is the first report on such CPL activity in the solid state with a rigorous protocol to exclude artifacts. Paramagnetic NMR spectroscopy revealed the nature and structure of the active species.

We review the present status of experiments and calculations for circularly polarized luminescence (CPL) of simple organic molecules and of stimuli-responsive organic molecules. Together with the historical report of the main instrumental approaches, a few crucial points about experiments are tackled, with the aim of defining measurement protocols, in view of the wide availability of commercial apparatuses in the near future. The calculations aimed at interpreting the CPL spectra, mostly based on time-dependent Density Functional Theory (TD-DFT) calculations, which started around 2010, are reviewed, limiting the discussion to small to mid-sized molecules. Some applications of CPL spectra of organic molecules-based systems are presented, with a focus especially on two fields: material science and biology. Chirality 28:696-707, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT UV, circular dichroism (CD), fluorescence and circularly polarized luminescence (CPL) spectra were recorded for a set of four related [2.2.1] bicyclic compounds ((1 S,4 S)-and (1 R,4 R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one, namely (1 S)- and (1 R)-camphor ( 1), (1 S,4 R)-4,7,7-trimethylbicyclo[2.2.1]hept-5-en-2-one, (1 S)-dehydro-epicamphor ( 2), (1 S,4 S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,5-dione, (1 S)-5-oxocamphor ( 3), (1 S,4 R)- and (1 R,4 S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione, (1 S)- and (1 R)-camphorquinone ( 4)) and a set of three related [2.2.2] bicyclic compounds (1 S,4 S)-bicyclo[2.2.2]octan-2,5-dione (saturated diketone ( 5)), (1 R,4 R)-bicyclo[2.2.2]oct-7-en-2,5-dione (unsaturated diketone ( 6)), ((1 S,4 S)-bicyclo[2.2.2]oct-7-en-5( S)-ol-2-one (which we refer to as unsaturated hydroxy-ketone ( 7)). For the latter three compounds also mid-IR vibrational circular dichroism (VCD) spectra were recorded and are presented. Time-Dependent Density Functional (TD-DFT) calculations provide a satisfactory interpretation of both absorption and emission chiroptical spectra and permit insight into ground and excited state electronic properties. We discuss the applicability of the octant rule or of other approximated models to rationalize the observed sign of the CPL. Chirality 25:589-599, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]