The reduction of the bulky amido-germanium(II) chloride complex, LGeCl (L = N(SiMe(3))(Ar*); Ar* = C(6)H(2)Me{C(H)Ph(2)}(2)-4,2,6), with the magnesium(I) dimer, [{((Mes)Nacnac)Mg}(2)] ((Mes)Nacnac = [(MesNCMe)(2)CH](-); Mes = mesityl), afforded LGeGeL, which represents the first example of a digermyne with a Ge-Ge single bond. Computational studies of the compound have highlighted significant electronic differences between it and multiply bonded digermynes. LGeGeL was shown to cleanly activate H(2) in solution or the solid state, at temperatures as low as -10 °C, to give the mixed valence compound, LGeGe(H)(2)L.

The long and the short of it. The first amido–digermyne to possess a short Ge–Ge multiple bond, [LGeGeL], has been prepared and shown to activate H2 below 0 °C, thereby yielding the hydrido–digermene, [L(H)GeGe(H)L]. This possesses a very long GeGe bond. Spectroscopic and theoretical data indicate that the dimer dissociates in solution to give the two‐coordinate hydrido–germylene, [:Ge(H)(L)]. L=N(Ar)(SiiPr3), Ar=2,6‐[C(H)Ph2]2‐4‐iPrC6H2.

Taking the fizz out: A digermyne compound with a Ge-Ge single bond has been shown to quantitatively reduce CO(2) to CO at temperatures as low as -40 °C. The mechanism of this unprecedented reaction has been probed by spectroscopic and computational techniques and involves a metastable intermediate (see picture; Ar*=C(6) H(2){C(H)Ph(2)}(2)Me-2,6,4).

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The preparation of a series of extremely bulky secondary amines, Ar*N(H)SiR(3) (Ar* = C(6)H(2){C(H)Ph(2)}(2)Me-2,6,4; R(3) = Me(3), MePh(2) or Ph(3)) is described. Their deprotonation with either LiBu(n), NaH or KH yields alkali metal amide complexes, several monomeric examples of which, [Li(L){N(SiMe(3))(Ar*)}] (L = OEt(2) or THF), [Na(THF)(3){N(SiMe(3))(Ar*)}] and [K(OEt(2)){N(SiPh(3))(Ar*)], have been crystallographically characterised. Reactions of the lithium amides with germanium, tin or lead dichloride have yielded the first structurally characterised two-coordinate, monomeric amido germanium(II) and tin(II) chloride complexes, [{(SiR(3))(Ar*)N}ECl] (E = Ge or Sn; R = Me or Ph), and a chloride bridged amido-lead(II) dimer, [{[(SiMe(3))(Ar*)N]Pb(μ-Cl)}(2)]. DFT calculations on [{(SiMe(3))(Ar*)N}GeCl] show its HOMO to exhibit Ge lone pair character and its LUMO to encompass its Ge based p-orbital. A series of bulky amido silicon(IV) chloride complexes have also been prepared and several examples, [{(SiR(3))(Ar*)N}SiCl(3)] (R(3) = Me(3), MePh(2)) and [{(SiMe(3))(Ar*)N}SiHCl(2)], were crystallographically characterised. The sterically hindered group 14 complexes reported in this study hold significant potential as precursors for kinetically stabilised low oxidation state and/or low coordination number group 14 complexes.

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We present a first-principles theoretical study on the dissociative chemisorption of tris(dimethylamino)silane (TDMAS) on a hydroxylated SiO 2 (001) surface. The thermochemical energies and activation barriers associated with the elementary surface reaction processes have been calculated. Our results indicate that sequential dissociation of TDMAS can occur only up to the second step with dimethylaminosilylenyl groups anchored on the surface. Further dissociation of these surface species is virtually energetically forbidden under typical atomic layer deposition processing conditions. This would result in an inherently low density and compositionally impure SiO 2 film with a low deposition rate.

Organic ionic plastic crystal (OIPC) modified poly(vinylidene difluoride) (PVDF) composite fiber membrane with enhanced ion dynamics and almost pure β-PVDF are demonstrated.