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Two dinuclear lanthanide complexes (Gd and Dy) were prepared and characterized by X-ray, magnetic and computational methods. The Dy analogue shows SMM behavior with an energy barrier of 98.4 K in the absence of an applied dc field. Theoretical calculations were performed on model complexes which support the hypothesis that the energy barrier will increase if the soft-donor atoms S and Se are used in lieu of an O donor.

We present the synthesis, structure, and electrochemistry of K 3 [Mo 2 (SNO5) 4 Cl] 3 [Mo 2 (SNO5) 4 ] (1, HSNO5 = monothiosuccinimide), the first example of a heterometallic extended metal atom node (HEMAN). The HEMAN consists of two perpendicular, intersecting lines of metal atoms formed by three [Mo 2 (SNO5) 4 Cl] - units and one [Mo 2 (SNO5) 4 ] unit tethered together by K + ions.

Two new strongly AEE active (I/I0 ≈ 94) tetraphenylsilole-containing cyclosiloxanes with cyan emissions (λem = 500 nm) and ∼100% solid state fluorescence quantum yields are reported. The intra- and intermolecular C-Hπ interactions in the crystal play a major role in the observed high solid state fluorescence quantum yields.

We report an exploration of the coordination chemistry of a systematic series of cyclic thioamidate ligands with the quadruply-bonded Mo2(4+) core. In addition to the S and N donor atoms that bind to Mo, the ligands utilized in this study have an additional O or S atom in conjugation with the thioamidate π system. The preparation of four new Mo2 complexes is described, and these compounds are characterized by X-ray crystallography, NMR and UV-vis spectroscopy, electrochemistry, and DFT calculations. These complexes provide a means to interrogate the electronics of Mo2(thioamidate)4 systems. Notably, we describe the first two examples of Mo2(thioamidate)4 complexes in their cis-2,2-regioisomer. By varying the π-system substituent and regioisomerism of these compounds, the electronics of the dimolybdenum core is shown to be altered with varying degrees of effect. Cyclic voltammetry results show that changing the π-system substituent from O to S results in an increase in the Mo2(4+/5+) oxidation potential by 170 mV. Changing the arrangement of ligands around the dimolybdenum core from trans-2,2 to cis-2,2 slightly weakens the metal-ligand bonds, raising the oxidation potential by a more modest 30-100 mV. MO diagrams of each compound derived from DFT calculations support these conclusions as well; the identity of the π-system substituent alters the δ-δ* (HOMO-LUMO) gap by up to 0.4 eV, whereas regioisomerism yields smaller changes in the electronic structure.