Bonds Sharing Electrons

Carbon, silicon, and germanium neither lose nor gain. They share electrons with other atoms. Tin and lead are too large to form the close electron-sharing bonds of the other three. They lose electrons to form +2 or + 4 ions. 

Covalent bonding wherein two atoms of the same, or of differing elements, share one or more electron(s) from each atom in order to unite to form an electron shared bond between the two atoms. 

Dative covalent bonding wherein a similar electron shared bond occurs but all of the electrons are provided by the atom at one end of the bond. 

Weak-electron sharing bonding In magnitude, this is of the same value as the hydrogen bond. It is also the Lewis acid-Lewis base bond (comparable to Brpnsted acids and bases). Such forces might contribute appreciably to cohesiveness at interfaces a typical example is the weak association of iodine (I2) with benzene or any polyaromatic compound. The interaction is the donation of the electrons of I2 to the electron-deficient aromatic molecules (jr-electrons). 

Covalent bonds form when atoms share electrons. Since electrons move very fast they can be shared, effectively filling or emptying the outer shells of the atoms involved in the bond. Such bonds are referred to as electron-sharing bonds. An analogy can be made to child custody the children are like electrons, and tend to spend some time with one parent and the rest of their time with the other parent. In a covalent bond, the electron clouds surrounding the atomic nuclei overlap. 

The occurrence of two energy minima for C(BH)2 shows that isomers which have electron-sharing bonds HB=C=BH and donor-acceptor bonds HB->C<-BH may lead to coexisting species that can be experimentally identified through their different vibrational spectra [27]. The different bonding situations come to the fore when the occupied valence orbitals of the two isomers, which are shown in... 

Figure 4.11 Schematic representation of (a) the donor-acceptor bonding in NHC P- SiClj and (b) electron-sharing bonding in Cl2Si(CAAC P)2- The energies were calculated at the M05-2X/def2-TZVPP//M05-2X/SVP level of theory. (The data are taken from Ref [38].)...

Valence Orbitah and Hybridization in Electron-Sharing Bonds of Transition Metals 1177... 

Chemical bonding Dative bond Electron-sharing bond ... 

The review by Haaland [20] is a good starting point for the present manuscript. It summarizes the knowledge of classical Lewis acid/base complexes mainly of group 13/15 adduct which were known at that time. It is shown that the discrimination between electron-sharing bonds and dative bonds is very useful for understanding molecular structures and stabilities. But during the last decade, it was realized that... 

Fig. 1 Sketch of electron-pair bonds in CO2 and C3O2 with electron-sharing bonds and dative bonds. Below each structure are the electronic reference states of the atoms and CO for the respective bonding interactions. At the bottom are the excitation energies from the electronic ground state to the excited state which were taken from [61]...

D excitation energies for two oxygen atoms entail 2 x 45.4 = 90.8 kcal/mol and the P excitation of carbon necessitates another 29.1 kcal/mol. Thus, a total of 119.9 kcal/mol is required to promote oxygen and carbon for possible donor-acceptor interactions Ot C O, while only 96.4 kcal/mol is necessary for electron-sharing bonds 0=C=0. Since electron-sharing bonds are stronger than dative bonds between the same atoms, it is clear that CO2 should be written as... 

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