Introducing an unprecedented nucleating and phasing agent for protein crystallography that presents convenient luminescence properties.

The synthesis and the molecular and photophysical characterization, together with solid state and solution structure analysis, of a series of europium complexes based on β-diketonate ligands are reported. The Eu(III) complex emission, specifically its photoluminescence quantum yield (PL-QY), can be tuned by changing ligands which finely modifies the environment of the metal ion. Steady-state and time-resolved emission spectroscopy and overall PL-QY measurements are reported and related to geometrical features observed in crystal structures of some selected compounds. Moreover, paramagnetic NMR, based on the analogous complexes with other lanthanides, are use to demonstrate that there is a significant structural reorganization upon dissolution, which justifies the observed differences in the emission properties between solid and solution states. The energy of the triplet levels of the ligands and the occurrence of nonradiative deactivation processes clearly account for the luminescence efficiencies of the complexes in the series.

The electronic structure of a chiral Yb(III)-based complex is fully determined by taking advantage of experimental magnetic, luminescence, and chiroptical (NIR-ECD and CPL) characterizations in combination with ab-initio wavefunction calculations....

The CD spectra of 13 crystalline aryl benzyl sulfoxides 1a-m with various substituents on the two aromatic rings were recorded in solution and in the solid state. Solution CD spectra were very homogeneous along the series, consisting in most cases of a couplet-like feature in the 200-300 nm region. The red-shifted component of the couplet, corresponding to the sulfoxide-centered n-pi* transition, is always positive for (R) absolute configuration in accordance with Mislow's rule. The presence of a strong electron-withdrawing substituent on the phenyl ring (nitro or ester group) alters the shape of the CD spectrum. CD calculations using the TDDFT method were run for eight representative compounds using DFT-optimized geometries. In all cases, calculated spectra were in very good agreement with experimental ones and allowed for rationalization of the diverse spectral behaviors. It is demonstrated that TDDFT//DFT calculations represent a reliable option for assigning the absolute configuration of this class of compounds whenever crystals suitable for X-ray are not available. Solid-state CD spectra recorded with the KCl pellet technique were in some cases in agreement with those in solution. However, in other cases new and strong CD signals appeared which were interpreted as being due to intermolecular couplings in the crystals.

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Luminescent lanthanide‐doped oxides, nanoparticles, nanocrystals, and coordination complexes are major tools in the fields of optical and laser materials, telecommunications, medical imaging, and fluoroimmunoassays. In particular, coordination complexes are efficient energy converters with high photostability, large ligand‐induced Stokes shifts, and tunable excitation and emission spectra. However, their application as light downshifting materials for solar cells has not yet been widely explored. This third generation solar cell concept enables to increase the efficiency of standard solar cells—such as Si or copper indium gallium (di)selenide (CIGS)—that have low performance for ultraviolet photons. The incorporation of such a converter in solar module encapsulants can provide a cheap and effective way to integrate photon conversion. Here, encapsulants functionalised by photon downshifting coordination complexes have been spin‐coated on silicon solar cells. For all the coordination complexes, an increase of the spectral response of the solar cells is observed in the ultraviolet region. In the best case, a relative increase of 8% of the conversion efficiency of the solar cell is observed. Copyright © 2016 John Wiley & Sons, Ltd.

The heterobimetallic complex CsEu[(+)-hfbc](4) (hfbc = 3-heptafluorobutyryl camphorate), prepared by Kaizaki and co-workers, displays the highest ratio of polarization versus total luminescence (measured by the g(lum) factor), i.e., ~85% of the emitted photons at 595 nm are left-circularly polarized. We present a detailed structural analysis in solution, based on paramagnetic nuclear magnetic resonance (NMR), and discuss the possible dynamic processes, where its analogues are involved. We demonstrate that the first coordination sphere is very close to the achiral regular square antiprism (SAPR) with D(4d) symmetry, which rules out the intrinsic dissymmetry of the Eu environment for rationalizing the g(lum). In contrast, the dynamic coupling between the f-f transitions, responsible for the emission, to the ligand-centered π-π* transition at 310 nm displays almost ideal geometry to justify g(lum) and discloses a key to high circularly polarized emission.

The structural elucidation of the compounds isolated from the endophytic Phomopsis sp. revealed phomopsinones A-D (1-4), four new α-pyrone derivatives. Three known compounds were also isolated, namely two phomosines, phomosine A (5) and phomosine C (6), and ergosterol (7). The structures of these compounds were determined by spectroscopic analysis ( 1H, 13C, 1H- 1H COSY, HMQC, HMBC, and ROESY NMR, and mass spectrometry), supported by molecular modeling. The absolute configurations of the new compounds 1-4 were determined by circular dichroism spectroscopy and TDDFT calculations. Preliminary studies indicated that compounds 1 and 4 show strong and good antifungal activity, respectively. Similarly, compounds 2 and 3 showed good antifungal and moderate antibacterial activities as well as antialgal activities