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[1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.
Tetraoxygen was first predicted in 1924 by Gilbert N. Lewis, who proposed it as an explanation for the failure of liquid oxygen to obey Curie's law. [1] Though not entirely inaccurate, computer simulations indicate that although there are no stable O 4 molecules in liquid oxygen, O 2 molecules do tend to associate in pairs with antiparallel spins, forming transient O 4 units. [2]
Lewis structures (or "Lewis dot structures") are flat graphical formulas that show atom connectivity and lone pair or unpaired electrons, but not three-dimensional structure. This notation is mostly used for small molecules. Each line represents the two electrons of a single bond. Two or three parallel lines between pairs of atoms represent ...
Under the framework of valence bond theory, resonance is an extension of the idea that the bonding in a chemical species can be described by a Lewis structure. For many chemical species, a single Lewis structure, consisting of atoms obeying the octet rule, possibly bearing formal charges, and connected by bonds of positive integer order, is sufficient for describing the chemical bonding and ...
[4] 1,3,5-Trinitrobenzene and related polynitrated aromatic compounds are often described as electron-deficient. [5] Electron deficiency can be measured by linear free-energy relationships : "a strongly negative ρ value indicates a large electron demand at the reaction center, from which it may be concluded that a highly electron-deficient ...
When it is converted to the covalent red phosphorus, the density goes to 2.2–2.4 g/cm 3 and melting point to 590 °C, and when white phosphorus is transformed into the (also covalent) black phosphorus, the density becomes 2.69–3.8 g/cm 3 and melting temperature ~200 °C. Both red and black phosphorus forms are significantly harder than ...
Gilbert Newton Lewis ForMemRS [1] (October 23 [2] [3] [4] or October 25, 1875 – March 23, 1946) [1] [5] [6] was an American physical chemist and a dean of the college of chemistry at University of California, Berkeley.
A center dot may also be used to represent a Lewis adduct, such as Me 3 B·NH 3. Another example is boron trifluoride diethyl etherate , BF 3 ·Et 2 O . In a slightly different usage, the center dot is also used to represent hydrate coordination in various crystals, as in MgSO 4 ·7H 2 O for hydrated magnesium sulfate , irrespective of whether ...