Major Crystallographic Directions Research Articles

Directional Effects in Electron Irradiated Cu Single Crystals

AbstractThin copper single crystal samples have been irradiated by energetic electrons which were incident along major crystallographic directions. Appreciable defect production was observed in samples oriented for 〈100〉 and 〈110〉 incidence in the near‐threshold range, indicating that threshold displacement energies for both directions are comparable. Postirradiation studies have shown that recovery takes place throughout the entire Stage I temperature range, even at the lowest electron energies.

Infrared Spectra of Inorganic Dielectric Solids

The lattice vibration spectrum of a solid has recently been characterized by one single frequency, which is defined as the frequency of the center of gravity of the spectrum, called “centro-frequency”. Here the experimental determination of this frequency is shown in detail for a number of solids the vibrational spectra of which became available recently. Emphasis is given to spectral data at various temperatures, from 4°K to about 1000°K, and at the various major crystallographic directions. The “centro-frequencies” at room temperature and higher temperatures show almost no change; whereas, at low temperature, the “centro-frequencies” consistently show a very definite increase. The result reveals a definite increase in binding energy with temperature decrease. A considerably higher resolution, particularly in the broad band areas, was obtained with spectra at very low temperatures.