Lateral overlap, orbitals

Lactone intermediates, 94,127, 228 Lateral overlap, orbitals, 9 Lead alkyls, 301 anti-knock, 305 thermolysis, 301, 304, 324 Leaving groups, 98, 99, 127,139, 237 ability of, 98, 251... 

With both (la) and (2a) above, lateral overlap of the p atomic orbitals on adjacent carbon atoms could lead to the formation of two localised n bonds as shown, and the compounds would thus be expected to resemble ethene, only twice as it were This is indeed found to be the case with (2), but (1) is found to behave differently in terms of its slightly greater stability (referred to above), in spectroscopic behaviour (see below), and in undergoing addition reactions more readily than does an isolated diene (p. 194). On looking more closely, however, it is seen that with (la), but not with (2a), lateral overlap could take place between all four p atomic orbitals on adjacent carbon atoms. Such overlap will result in the formation of four molecular orbitals (Fig. 1.2), two bonding ( and 2) and two anti-bonding (i//3 and 4)—the overlap of n atomic orbitals always gives rise to n molecular orbitals ... 

How then is the positive charge in the (OC)9Co3C-substituted carbonium ions delocalized into the cluster substituent In our first preliminary report on this new class of carbonium ions (45), we suggested that their structure presents an especially favorable opportunity for lateral overlap of a filled er-bonding orbital of a metal-carbon bond and a vacant p orbital on an electron-deficient carbonium ion center /3 to the metal (VIII), that is believed responsible for the high... 

Formed by head-to-head overlap of AO s. 1. Formed by lateral overlap of p orbitals (or p and d orbitals). 

Fig. 48. Formation of a bond in ethylene a bonds omitted). If the two 2p orbitals are parallel there is substantial lateral overlap (for clarity not shown in the Fig.) giving a 71 bond rotation of the CIL groups lessens the bonding.

Phosphorus Pentoxide (P4O10) In this each P atom forms three bonds to the oxygen atoms and also an additional coordinate bond with an oxygen atom. Terminal PO bond is much shorter than PO bond. It shows that there is a considerable pp-dp back bonding because of the lateral overlap of full p-orbitals on oxygen with empty Jp-orbitals on phosphorus. 

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