"Attempts to regard a molecule as consisting of specific atoms or ionic units held
together by discrete numbers of bonding electrons or electron pairs are considered
as more or less meaningless."
Robert Mulliken. Selected Papers of Robert S. Mulliken, D.A. Ramsay and J. Hinze, eds., p. 451. 1932.
"The paper of Heitler and London on H2 for the first time seemed to provide a basic understanding, which could be extended
to other molecules. Linus Pauling at the California Institute of Technology in Pasadena
soon used the valence bond method. . . . As a master salesman and showman, Linus persuaded
chemists all over the world to think of typical molecular structures in terms of the
valence bond method."
Robert Mulliken. Life of a Scientist, pp. 60-61. 1989.
"Pasadena at that time seemed an earthly paradise, with good science too. We had a
dip in the Pacific Ocean at Christmas . Although Pauling and I were at that
time rivals on the subject of valence bond theory, we had friendly relations with
the Pauling family: Linus and Ava Helen one day took us for a memorable expedition
into the desert."
Robert Mulliken. Life of a Scientist, pg. 97. 1989.