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We review the current understanding of superconductivity in the quasi-one-dimensional organic conductors of the Bechgaard and Fabre salt families. We discuss the interplay between superconductivity, antiferromagnetism, and charge-density-wave fluctuations. The connection to recent experimental observations supporting unconventional pairing and the possibility of a triplet–spin order parameter for the superconducting phase is also presented.

We describe a crossed electron beam‐atomic beam apparatus which utilizes a pulsed electron gun and field free drift tube to obtain time‐of‐flight (TOF) spectra of electrons scattered from atoms and molecules. This apparatus was constructed for the purpose of obtaining inelastic‐to‐elastic differential cross‐section (DCS) ratios in the energy range extending from threshold to several eV above the threshold of the inelastic channel. The TOF approach eliminates the need for complicated calibration procedures required when using conventional electrostatic electron energy‐loss spectroscopy (EELS) at these low energies. The characteristics of the apparatus will be given, along with representative TOF spectra from carbon monoxide. From those spectra we obtained DCS ratios at 90° scattering angle for excitation of the a3Π state of CO, in the impact energy range of 6–15 eV. These ratios were measured with uncertainties as small as ±4%, which represents a substantial improvement over previous measurements in this e...

Small‐angle double‐Bragg x‐ray scattering has been used for the study of recrystallization kinetics and angular misorientation of the mosaic structure in cold‐worked nickel and iron foil. The scattering measurements showed that short time recrystallization in nickel took place by growth of initial blocks with an activation energy of 2.2 ev. The use of a getter during the vacuum anneal increased the growth rate by a factor of 1000. Angular misorientation was found to be associated with work hardening in both nickel and iron.

The average small angle double Bragg scattering from moderately cold‐worked polycrystalline metals has been calculated ignoring extinction. The predicted scattering is of the correct order of magnitude. Tests involving dependence on grain size prior to cold work, density of the metal, degree of plastic deformation, and anisotropy have been made and appear to agree with the calculation.

A theory describing the interaction between electron‐density fluctuations and the main dipole resonance of the Dattner spectrum is presented. The results of the theory are compared with experiment, and it is found that the fluctuations can substantially modify the resonance shape.

The splitting of the Tonks‐Dattner resonances in an axial magnetic field is considered. It is found that the higher‐order resonances are split and decompose into left‐ and right‐circularly polarized modes. Experiments at higher magnetic fields are described in which the Buchsbaum‐Hasegawa resonances are also observed. These resonances appear to be right‐circularly polarized.