Germanium oxide , crystal structure

In the absence of light, diorgano germanium porphyrin complexes are stable but have long been known to react with oxygen. The products of this oxidation process have been formulated speculatively as germanium-bound peroxyalkyl complexes " an assignment confirmed by the report of the crystal structure of (TPP)Ge(02R)2 (R = Et, Bu ). ... 

Oxidation of the germanium(II) azide [GeN3(Tp )] with HN3 selectively yielded [Ge(N3)3(Tp )] (Fig. 2.142), the crystal structures of which have been determined and compared with those of other six-coordinate germanium(II) polyazides.583 [GeCl(Tpx)] derivatives were reported before 1999.584,585... 

Sayers DE, Hesterberg D, Zhou W, Robarge WP, Plummer GM (1997) XAFS characterization of copper contamination in the unsaturated and saturated zones of a soil profile. J de Physique IV 7 (Colloque C2, X-Ray Absorption Fine Structure, Vol. 2) 831-832 Sayers DE, Lytle FW, Stem EA (1972) Structure determination of amorphous germanium, germanium oxide, and germanium selenide by Fourier analysis of extended X-ray absorption fine structure (EXAFS). J Non-Crystal Solids 8-10 401-407... 

Porphyrin complexes, (porph)Ge and (porph)GeCl2, are known for the +2 and +4 oxidation states. Reaction of phthalocyanine with GeCl4 in quinoline gives the highly stable complex (phthalo)GeCl2 in which the two Cl atoms are necessarily trans. It sublimes without decomposition at 450 °C. Recently, the crystal structure of bis(acetato)(/He50-tetraphenylporphyrinato) germanium (IV), Ge (tpp) (0 Ac) 2... 

Sulfide Molecular Sieves. All crystalline molecular sieves and microporous crystals have so far been based on oxide frameworks. As discussed previously, the oxide-based molecular sieve family shows rich compositional and structural diversity, and the number of new species is still growing at a rapid rate. An important new direction for molecular sieves is provided by the recent discovery of sulfide-based molecular sieves. The first publication on these materials already described a whole family of sulfide molecular sieves containing germanium (Ge) and tin (Sn) or several other metals. The crystal structures are all new and include 12 unique framework structures. These materials may have potential applications using sulfur-containing feedstocks in which the sulfur present may stabilize the composition of the sulfide molecular sieve. 

A bis(chelate) structure was found for the closely related germylene [MeC(NPr )2]2Ge, which was also made from GeCl2(dioxane) and 2 equivalents of the lithium amidinate (colorless crystals, 81%). The same synthetic approach was used to make bis(amidinato) metal dichlorides of silicon and germanium in high yields (83-95%). Rapid oxidative addition of chalcogen atom sources (styrene sulfide and elemental Se) to the germylene derivatives resulted in a series... 

We begin by reviewing the surface structure of the most commonly studied crystal faces of these materials. We will then briefly discuss the oxidation of both silicon and germanium, then review the passivation of silicon and germanium surfaces. In addition, we explore the reactivity of Si, Ge, and to a lesser extent GaAs and InP, toward various organic molecules that can be used to functionalize the surface and impart new properties to the semiconductor. 

The spectrum of energy levels for electrons at the germanium surface usually differs from that in the interior of the crystal. This situation arises because of the unsaturated energy levels of the surface atoms, misfits in the structures of germanium and the oxide, and other impurities like chemisorbed gases. All these factors, either independently or combined together, result in the formation of the... 

The reactions of germanium with oxygen and with nitrogen are reviewed. Particular emphasis has been placed on the relationship between the structure and electronic properties of the oxide and nitride films formed on single crystal germanium surfaces under different processing conditions. A summary of the electronic properties reported is presented and some conclusions are offered based on the recent literature. 

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