HEITLER W. & F. LONDON.

Wechselwirkung neutraler atome und homöopolare Bindung nach der Quantenmechanik.

Berlin, Julius Springer, 1927. 8vo. In contemporary half cloth with gilt lettering to spine. In "Zeitschrift für Physik", Vol. 44. Entire volume offered. Stamp to front free end paper, otherwise a fine and clean copy. Pp. 455-472. [Entire volume: VIII,903 pp.].

First appearance of grounbreaking paper which was the first to explain the nature of the chemical bound using wave mechanics and thus explaining the forces active when atoms exchange electrons and creating molecules.

"In June, Heitler and London published their famous paper on the hydrogen molecule in which they showed the existence of a new kind of saturable, nondynamic forces, the so-called "exchange forces" of attraction or repulsion between like particles, and developed a schematic theory of the homopolar valence which eventually BROUGHT THE WHOLE OF CHEMISTRY UNDER THE SOVEREIGNTY OF QUANTUM MECHANICS. These results not only lent weight to the concept of like particles, they also showed that like particles may be indistinguishable, that is, may lose their identity, a conclusion which follows from the uncertainty relations or, more precisely, from the impossibility of keeping track of the individual particles in case of interactions of like particles. (Jammer in "The Conceptual Development of Quantum Mechanic", pp. 343 ff.).

Parkinson "Breakthroughs" 1927 C.

Order-nr.: 49387