Organic molecules with heavy main-group elements frequently form supramolecular links to electron-rich centres. One particular case of such interactions is halogen bonding. Most studies of this phenomenon have been concerned with either dimers or infinitely extended structures (polymers and lattices) but well-defined cyclic structures remain elusive. Here we present oligomeric aggregates of heterocycles that are linked by chalcogen-centered interactions and behave as genuine macrocyclic species. The molecules of 3-methyl-5-phenyl-1,2-tellurazole 2-oxide assemble a variety of supramolecular aggregates that includes cyclic tetramers and hexamers, as well as a helical polymer. In all these aggregates, the building blocks are connected by Te…O–N bridges. Nuclear magnetic resonance spectroscopic experiments demonstrate that the two types of annular aggregates are persistent in solution. These self-assembled structures form coordination complexes with transition-metal ions, act as fullerene receptors and host small molecules in a crystal.

Electron-donating N-heterocyclic carbenes (Lewis bases, LB) and electron-accepting Lewis acids (LA) have been used in tandem to yield donor–acceptor complexes of inorganic tetrelenes LB·EH2·LA (E = Si, Ge, and Sn). Herein, we introduce the new germanium (II) dihydride adducts ImMe2·GeH2·BH3 (ImMe2 = (HCNMe)2C:) and ImiPr2Me2·GeH2·BH3 (ImiPr2Me2 = (MeCNiPr)2C:), with the former complex containing nearly 40 wt % germanium. The thermal release of bulk germanium from ImMe2·GeH2·BH3 (and its deuterated isotopologue ImMe2·GeD2·BD3) was examined in solution, and a combined kinetic and computational investigation was undertaken to probe the mechanism by which Ge is liberated. Moreover, the thermolysis of ImMe2·GeH2·BH3 in solution cleanly affords conformal nanodimensional layers of germanium as thin films of variable thicknesses (20–70 nm) on silicon wafers. We also conducted a computational investigation into potential decomposition pathways for the germanium­(II)- and tin­(II)-dihydride complexes NHC·EH2·BH3 (NHC = [(HCNR)2C:]; R = 2,6-iPr2C6H3 (Dipp), Me, and H; and E = Ge and Sn). Overall, this study introduces a mild and convenient solution-only protocol for the deposition of thin films of Ge, a widely used semiconductor in materials research and industry.

The molecular precursor Ge(OtBu)2 was combined with soluble hydride sources to either yield metastable [GeH2]n materials (orange solids) or the deposition of nanoscale films of Ge from solution.

The University of Alberta Working for Inclusivity in Chemistry (UAWIC) group was formed in 2017 to bridge the gap in support for underrepresented groups between youth recruitment initiatives and professional organizations. UAWIC tailors its events and initiatives to the needs of the Department of Chemistry. With the goals of fostering a community amongst department members and retaining a diverse graduate student population, UAWIC has created initiatives addressing equity, diversity and inclusivity issues, professional development, and promoting visibility of diversity within the department. Training students how to overcome systemic barriers and providing platforms to share experiences will help aspiring chemists prepare for future career paths and develop a network of mentors and colleagues.

We report mild routes for the deposition of crystalline films of elemental tin via the formation and subsequent decomposition of unstable tin(II) hydrides. Specifically, we take advantage of efficient OtBu/H...