Structure and Magnetic Properties of Homoleptic Trivalent Tris(alkyl)lanthanides.

Six new solvent-free, homoleptic paramagnetic tris(alkyl)lanthanides Ln{C(SiHMe)} () and Ln{C(SiHMe)Ph} () (Ln = Gd, Dy, and Er) were synthesized to investigate the magnetic properties of 4f organometallic compounds stabilized by secondary Ln↼H-Si and benzylic interactions. The unit cell of contains one independent molecule ( = 2), while and crystallize with four independent isostructural molecules per unit cell ( = 16). In all molecules, as in other compounds, the three tris(dimethylsilyl)methyl ligands form a trigonal planar LnC core, and six secondary interactions involving Ln↼H-Si bonding in Ln{C(SiHMe)} form above and below the equatorial plane.

A fluorene-modified porphyrin for efficient dye-sensitized solar cells.

Porphyrins bearing a polyaromatic or a heterocyclic group are prepared to study their fundamental and photovoltaic properties. Solar cells sensitized with a fluorene-modified porphyrin outperform other dyes in the series, reaching ~90% efficiency of N719 dye.