Chemical bonding molecular orbital diagram

Fig. 15 A molecular OR gate, whose chemical structure maps the electrical circuit diagram shown in Fig. 20a. Two Aviram-Ratner molecular rectifier chemical groups have been bonded to a central chemical node. This intramolecular circuit with one simple node can be easily designed, because the node Kirchoff node law is valid here. Note that the molecular orbital of each partner can be still identified on the 2 T(E) because of their weak interactions through the CH2 bridge. This is not always the case. The obtained logic surface demonstrates an OR function for well-selected values of the input voltage, but with two logical level 1 outputs which would have to be corrected using an additional output circuit...

The term resonance does not mean that the molecule physically oscillates back and forth from one of these bonding structures to the other. Rather, within the limitations of the Lewis dot model of bonding, the best representation of the actual bonding is a hybrid diagram that includes features of each of the acceptable individual diagrams. This awkwardness can be avoided by using molecular orbital theory to describe chemical bonding (see Chapter 6). 

The diagram shows only the imeraciion with the energy state of ethane (the C-K bond). Other molecular orbitals of the ethane also distort. [Courtesy of R. Masel, Chemical Kinerics (McGraw Hill. 2002), p. 594 ]... 

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