NIELS BOHR’S GREATEST ACHIEVEMENT, A WORK WHICH “EFFECTIVELY CHANGED THE COURSE OF PHYSICS”

BOHR, Niels. "On the Constitution of Atoms and Molecules." IN: The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Volume 26, Numbers 151, 153, 155, pp. (1)-25; (475)-502; (857)-875. London: Taylor and Francis, 1913. . Thick octavo, modern three-quarter black morocco. $4500.

First edition of Niels Bohr’s landmark work “On the Constitution of Atoms and Molecules,” “the most valuable contribution which quantum theory has ever made to physical science” (J. J. Thomson).

"In 1913, while in England and working with Rutherford, Bohr published three papers that concerned atomic structure. They effectively changed the course of physics" (Simmons, The Scientific 100:3, 17). In this epoch-making and wide-ranging "trilogy" of papers, Bohr decisively demonstrated that classical mechanics could not explain the workings of the atom, and educed its electron structure. The first paper focused on the hydrogen atom, the second paper treated heavier atoms and the periodic table, and the third paper dealt with the structure of molecules. Bohr concluded that while electrons might follow a classical model in individual states, the classical model broke down in the transition between states. Bohr identified the "quanta" of energy needed to change states and related it to Planck's constant. Bohr's discoveries, along with Einstein's earlier work on relativity, represent the major cornerstones of quantum theory. Bohr was one of the first to recognize and indeed observe that Newton's models for the universe could not be applied without reservation at the atomic level. Einstein, who had initiated the skepticism regarding the universal application of Newtonian physics, identified Bohr's work as "an enormous achievement" (Simmons, 17). "Bohr's atomic theory inaugurated two of the most adventurous decades in the history of physical science. In 1924, Bohr completed the final revisions of his 1913 theory with the conviction that classical modes of description of atomic processes had to be relinquished" (Norman 258). "His proposal of a highly influential model of the atom laid the basis for quantum mechanics as it finally emerged at the end of the 1920's… The Rutherford-Bohr model of the atom, as it came to be known, was a fundamental advance, and soon was used to gain a new understanding of all the known atomic elements" (Simmons, 17). Bohr here, for example, identified the origins of X-ray spectra, which led in the following year to British physicist Henry Moseley's work subjecting each of the chemical elements to the X-ray spectral analysis and assigning to each an atomic number, thereby bringing a new, definitive order to the periodic table. More significantly, Bohr's insistence that the chemical properties of the elements depended on the outermost ring of electrons (and in particular valency) is the very basis for quantum chemistry. And Bohr's demonstration that beta-rays emanated from the nucleus, and not from the electron, constituted the first critical step toward nuclear physics. Bohr was awarded the 1922 Nobel Prize in physics "for his services in the investigation of the structure of atoms, and of the radiation emanating from them." Volume 26, Sixth Series; the three papers are in No.151 (pp.1-25), No.152 (pp.476-501) and No 155 (pp.857-75). Odelberg, 432.

Fine condition.