Double and Triple Bonds
Two different explanations for the nature of double and triple covalent bonds in organic molecules were proposed in the 1930s. Linus Pauling proposed that the double bond results from two equivalent bonds, which later came to be called banana bonds or tau bonds. Erich Hückel proposed a representation of the double bond as a combination of a sigma bond plus a pi bond. The Hückel representation is the better-known one, and it is the one found in most textbooks since the late-20th century. There is still some debate as to which of the two representations is better, although some theoretical chemists consider both models to be practically equivalent. In a 1996 review, Kenneth B. Wiberg concluded that "although a conclusive statement cannot be made on the basis of the currently available information, it seems likely that we can continue to consider the σ/π and bent-bond descriptions of ethylene to be equivalent." Ian Fleming goes further in a 2010 textbook, noting that "the overall distribution of electrons is exactly the same" in the two models.
Read more about this topic: Bent Bond
Famous quotes containing the words double, triple and/or bonds:
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“And DANTE searched the triple spheres,
Moulding nature at his will,
So shaped, so colored, swift or still,
And, sculptor-like, his large design
Etched on Alp and Apennine.”
—Ralph Waldo Emerson (1803–1882)
“We black women must forgive black men for not protecting us against slavery, racism, white men, our confusion, their doubts. And black men must forgive black women for our own sometimes dubious choices, divided loyalties, and lack of belief in their possibilities. Only when our sons and our daughters know that forgiveness is real, existent, and that those who love them practice it, can they form bonds as men and women that really can save and change our community.”
—Marita Golden, educator, author. Saving Our Sons, p. 188, Doubleday (1995)