Covalent inorganic compounds

Class A Type MX, . (Note We generally assume that the ligand is monovalent.) A small number of almost purely covalent inorganic compounds that are extracted by nonsolvating organic solvents. As these complexes are nonelectrolytes and almost as inert as the solutes of Type 1-A, they are treated jointly in section 4.4. 

Truly, the redox reaction concept in its simplest form, transfer of one or several electrons between two species, is much easier to apply to the central atoms of inorganic complexes and relatively simple covalent inorganic compounds with their well-defined oxidation states than to the carbon atoms of organic molecules. Nevertheless oxidation states of the latter can be defined using very simple rules (see, e.g. Hendrickson et al., 1970) and immediately reveal the possible redox nature of any transformation at a carbon atom. It is also true that redox mechanisms other than electron transfer—hydrogen atom or hydride transfer, oxygen transfer, displacement, etc.—should by their very... 

T7ery little has appeared in the literature concerning the radiation chemistry of covalent inorganic compounds in condensed phase. In the search for new, high energy oxidizers, it appears plausible that ion fragmentation, electron capture, ion-molecule reactions, and free radical combination reactions at low temperatures may be utilized. 

The melting points of covalent inorganic compounds are generally high (Table 4.9 gives a few values). Glass points and sinter temperatures are a fraction of the melting points and refractory solids can be sintered only at comparatively... 

Green JC, Green MLH, Parkin G (2012) The occurrence and representation of three-centre two-electron bonds in covalent inorganic compounds. J Chem Soc Chem Commun 48 11481-11503... 

LiAlH4, lithium tetrahydridoaluminate ("lithium aluminium hydride . so-called) is an excellent reducing agent in ether solution for both organic and inorganic compounds it may be used to prepare covalent hydrides SiH ether, for example... 

We shall now briefly describe the well-known temperature-independent Langevin diamagnetism of closed-shell ions, such as K+ and Cl in KCl and similar Inorganics, such as Si02, AI2O3, and the zeolites, as well as the covalent organic compounds. Since all such... 

Turning to macromolecular inorganic compounds, say ZnS, the two hypothetical ionic extremes are Zn2+S2- and Zn6-S6+ (an inverted, unusual formulation). We can imagine a continuous array of possible electron distributions between these extreme limits, one of which is the electron-pair covalent bonding state. The association of covalency with = Ay in Eqn. III.3 warrants non-polar formal MOs. However, a different situation arises when electrons are permitted to enter the empty MO skeleton. The electron-pair "covalent state corresponds to... 

The rational synthesis of peptide-based nanotubes by self-assembling of polypeptides into a supramolecular structure was demonstrated. This self-organization leads to peptide nanotubes, having channels of 0.8 nm in diameter and a few hundred nanometer long (68). The connectivity of the proteins in these nanotubes is provided by weak bonds, like hydrogen bonds. These structures benefit from the relative flexibility of the protein backbone, which does not exist in nanotubes of covalently bonded inorganic compounds. 

Organic compounds contain covalent bonds. In general, compared to inorganic compounds organic compounds have low melting and boiling points, tend to be flammable, have relatively low densities, do not dissolve readily in water, and are primarily nonelectrolytes. 

It has been shown in this chapter that most inorganic compounds are neither purely covalent nor purely ionic, but have a bond type intermediate between the two extremes. The bond will be more ionic the lower the ionization energy of the atom that has to form the positive ion and the greater the electron affinity of the other. 

It has been argued that although the Lewis picture of two electrons making up a covalent bond may work well for organic compounds, it cannot be successfully applied to the majority of inorganic compounds Jorgensen Top. Curr. Chem. 1984, 124. 1-31. 

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