Lewis valency

Trivalent ( classical carbenium ions contain an sp -hybridized electron-deficient carbon atom, which tends to be planar in the absence of constraining skeletal rigidity or steric interference. The carbenium carbon contains six valence electrons thus it is highly electron deficient. The structure of trivalent carbocations can always be adequately described by using only two-electron two-center bonds (Lewis valence bond structures). CH3 is the parent for trivalent ions. 

G. N. Lewis, J. Am. Chem. Soc. 38 (1916), 762 G. N. Lewis, Valence and the Structure of Atoms and Molecules (New York, The Chemical Catalog Co., 1923). As observed by Pauling (in note 51, p. 5), this remarkable work forms the basis of the modern electronic theory of valence. ... 

G. N. Lewis, Valence and the Structure of Atoms and Molecules (New York, Chemical Catalog Co., 1923). 

Ingold, "Significance of Tautomerism," pp. 312313 in Baker, citing Lewis, Valence, 139 Lowry,... 

Bond dissociation Bond Polar Nonpolar I I Lewis Valence... 

G. N. Lewis (above) conceived the octet rule while lecturing to a class of general chemistry students in 1902. He was also one of the two authors of a now classic work on thermodynamic, Lewis and Randall, Thermodynamics and the Free Energy of Chemical Substances (1923). (right) This is his original sketch. From G. N. Lewis, Valence, Dover Publications, Inc., New York, 1966. 

Lewis valence bond structures]. The methyl cation or methenium ion (CH3+) may be considered the parent of the trivalent carbocations. The trivalent carbocations are also stiU referred to as classical ions. 

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