Abstract

When a series of back reflection x-ray powder pictures of a freshly crushed coarse crystalline powder is taken, successive pictures exhibit a progressive change. Individual spots sharpen, diffuse portions of powder rings disappear, and the number of spots increases markedly with time. The increase in spots is not caused by breaking up of the particles. An account of the technique used for observing the effect is given. Experiments are described which indicate that the changes are definitely associated with the surface. The time rate of change increases with the hardness of the material and appears to be related to the degree of valance binding in the structure. A tentative explanation of the phenomenon is proposed which can account for all the observed effects.

© 1945 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Techniques in Applied Electron Microscopy*

Robert D. Heidenreich
J. Opt. Soc. Am. 35(2) 139-148 (1945)

Electro-Optical Properties of Colloids. II*

Bernhard W. Sakmann
J. Opt. Soc. Am. 35(1) 66-85 (1945)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (7)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription