The molecular structure of isocyanic acid from microwave and infra-red absorption spectra

Experimental investigations of the infra-red and microwave spectra of the slightly asymmetric rotor, HNCO, have been made, and the structure of the molecule has been determined

Studies in Microwave Spectroscopy

The theory of microwave spectroscopy is first presented in some detail. Following this, sources of errors in structure determinations based on moment of inertia data are considered, and approximate equations for estimating their effects are derived. A microwave spectroscope has been assembled and its design, construction, and operation are discussed. Microwave spectra in the region from 20 to 25 kmc have been obtained for HN14C12O16, and DN14C12O16. A rotational constant obtained from an infrared study of HNCO by L. H. Jones is combined with the microwave data to yield the interatomic distances and bond angle. High resolution studies of the spectra of HNCO and HNCS permit evaluation of their electric quadrupole coupling constants and qualitative deductions concerning their structures to be made. The molecular species CF3-C≡C-H, CF3-C13≡C-H, CF3-C13≡-H, and CF3-C≡C-D have been observed to absorb in the microwave region, and from the frequencies of these absorptions the C≡C and C-H distances are determined. In addition, the measured moments of inertia are employed to calculate consistent sets of the remaining three parameters in CF3-C≡C-H. The application of the electron diffraction data of W. F. Sheehan, Jr., to this problem to determine which set of parameters actually represents the structure is described. Stark effect measurements are presented which determine the dipole moments of HN14C12O16 in three vibrational states and of DNCO, OCS, H2CO, CHF3, and CHF3-C≡C-H in their ground states. Finally, attempts to obtain microwave spectra for several other compounds are briefly described.</p

EFFECT OF BORON-HYDROGEN SPIN-SPIN COUPLING ON THE PROTON MAGNETIC RESONANCE SPECTRA OF SOME OF THE BORANES

Author Institution: Varian AssociatesProton magnetic resonance spectra of several of the boranes have been studied and have, in general, yielded interesting results. However, the coupling between the nuclear spins of the $B^{11}$ nuclei and the protons results in an overlapping multiplet structure of the lines which has complicated the assignments. Experiments have been performed in which the $B^{11}$ nuclei were excited at their resonant frequency while the proton magnetic resonance spectra were obtained in the usual way. By this means, it has been possible to collapse the multiplet structures of the spectra and to verify the assignments as they would apply in the unsplit case. Spectra of diborane, borohydride ions, and pentaborane are offered as examples of the application of this technique

The Structure of HNCO from Microwave and Infrared Spectra

Author Institution: California Institute of TechnologyPresentations without an abstract printed in the proceedings do not have an abstract (image or text) in the Knowledge Bank record

Memoirs: a twentieth-century journey in science and politics

The story of Edward Teller is the story of the twentieth century. Born in Hungary in 1908, Teller witnessed the rise of Nazism and anti-Semitism, two world wars, the McCarthy era, and the changing face of big science. A brilliant and controversial figure whose work on nuclear weapons was key to the American war effort, Teller has long believed in freedom through strong defense, a philosophy reflected in his stance on arms control and nuclear policy. These extraordinary recollections at last reveal the man behind the headlines-passionate and humorous, devoted and loyal. In clear and compelling prose, Teller tells of the people, events, and ideas that shaped him as a scientist, beginning with his early love of music and math, and continuing with his study of quantum physics with Werner Heisenberg. Present at many of the pivotal moments in modern science, Teller also describes his friendships with some of the century's greatest minds-Einstein, Bohr, Fermi, Szilard, von Neumann, Oppenheimer-and offers an honest account of the development of the atomic and hydrogen bombs. He also offers a moving portrait of his childhood, his marriage and family life, and his friendship with physicist Maria Mayer. Writing about those aspects of his life that have had important public consequences-from his conservative politics to his relationships with scientists and presidents-Teller reveals himself to be a man with deep beliefs about liberty, security, and the moral responsibility of science