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CAOS aims to identify a series of chemical reactions which, from a starting compound, can produce a desired molecule. CAOS algorithms typically use two databases: a first one of known chemical reactions and a second one of known starting materials (i.e., typically molecules available commercially). Desirable synthetic plans cost less, have high ...
Furthermore, the Ge–Ge bond is primarily covalent, whereas the Ge–M bond usually has an equal mix of covalent and ionic nature. Exceptions to this are Cr, Mn, and Cu, where the ionic component is dominant because of smaller overlap with the 4s orbital of the M atom, leading to less stability. [ 19 ]
Rather, bond types are interconnected and different compounds have varying degrees of different bonding character (for example, covalent bonds with significant ionic character are called polar covalent bonds). Six years later, in 1947, Ketelaar developed van Arkel's idea by adding more compounds and placing bonds on different sides of the triangle.
These are four valence bond structures that can contribute to the VBT description of bonding in a hydrogen molecule. The Heitler-London (covalent) structure is the largest contributor, while the ionic structures are minor contributors. The triplet structure is a negligible contributor.
Combinatorial libraries are special multi-component mixtures of small-molecule chemical compounds that are synthesized in a single stepwise process. They differ from collection of individual compounds as well as from series of compounds prepared by parallel synthesis. It is an important feature that mixtures are used in their synthesis.
Hydrogen compounds are compounds containing the element hydrogen. In these compounds, hydrogen can form in the +1 and -1 oxidation states. Hydrogen can form compounds both ionically and in covalent substances. It is a part of many organic compounds such as hydrocarbons as well as water and other organic substances.
Both ionic and covalent iodides are known for metals in oxidation state +3 (e.g. scandium iodide is mostly ionic, but aluminium iodide is not). Ionic iodides MI n tend to have the lowest melting and boiling points among the halides MX n of the same element, because the electrostatic forces of attraction between the cations and anions are ...
In inorganic chemistry, Fajans' rules, formulated by Kazimierz Fajans in 1923, [1] [2] [3] are used to predict whether a chemical bond will be covalent or ionic, and depend on the charge on the cation and the relative sizes of the cation and anion. They can be summarized in the following table: