Conjugate theory

Berzelius s conjugate theory, 1,4 l,l -Bibismolane, 3,284 Bicapped pentagonal prisms... 

In his conjugate theory, which used terms and ideas corps copule borrowed from Gerhardt, Jons Jacob Berzelius (1779-1848) viewed metal-ammines as conjugated or copulated compounds consisting of ammonia and a conjugate or copula. The conjugate cannot be removed by reaction with an acid, and it neither decreases nor increases the saturation capacity of a base, that is, a metal conjugated with ammonia can still combine with other substances. 

Beryllium, bis(t ifluo oacetylacetone)-gas chromatography, 560 Berzelius s conjugate theory, 4 Bicapped pentagonal prisms repulsion energy coefficients, 34 twelve-coordinate compounds, 100 Bicapped square antiprisms repulsion energy coefficients, 33,34 ten-eoordinate compounds, 98 1, r-Binaphthyl, 2,2 -bis(diphenylphosphino)-complexes... 

Salem L 1966 Molecular Orbital Theory of Conjugated Systems (Reading, MA Benjamin)... 

Our first approach took resort in simple resonance theory [36, 37]. For each conjugated nr-system aU resonance structures were generated, such as those shown in Figure 7-5. 

The initial values, a, , are derived by correlations with dipole moments of a series of conjugated systems. The exchange integrals are taken from Abraham and Hudson [38] and are considered as being independent of charge. The r-charges are then calculated from the orbital coefficients, c,j, of the HMO theory according to Eq. (14). 

Salem, L., 1966. The Molecular Orbital Theory of Conjugated Systems. Benjamin, New York. Saunders, M., 1987. 7. Amer. Chem. Soc. 109, 3150. 

Because of the mentioned leveling effect of the solvent (or excess acid itself acting as such) the acidity cannot exceed that of its conjugate acid. In the case of water the limiting acidity is that of HsO. Proton-ated water, H30 (hydronium ion), was first postulated in 1907, and its preeminent role in acid-catalyzed reactions in aqueous media was first realized in the acid-base theory of Bronsted and Lowry. Direct experimental evidence for the hydronium ion in solution and in the... 

A familiar feature of the electronic theory is the classification of substituents, in terms of the inductive and conjugative or resonance effects, which it provides. Examples from substituents discussed in this book are given in table 7.2. The effects upon orientation and reactivity indicated are only the dominant ones, and one of our tasks is to examine in closer detail how descriptions of substituent effects of this kind meet the facts of nitration. In general, such descriptions find wide acceptance, the more so since they are now known to correspond to parallel descriptions in terms of molecular orbital theory ( 7.2.2, 7.2.3). Only in respect of the interpretation to be placed upon the inductive effect is there still serious disagreement. It will be seen that recent results of nitration studies have produced evidence on this point ( 9.1.1). 

In the Hiickel theory, the 7r-electron energy of a conjugated molecule can be expressed by the following equation ... 

---