An X-Ray Small-Angle Scattering Instrument

Abstract

An X-ray small-angle scattering instrument is described which is used for recording X-ray diffraction patterns or small-angle X-ray scattering curves in an angular region very close to the direct beam. The measurement of X-ray intensity is accomplished with standard geiger or scintillation counter techniques. The instrument is designed for use with a spot-focus or vertical-line X-ray source, In essence, it is a multiple-reflection double-crystal diffractometer, based on a concept developed by Bonse and Hart, employing two grooved perfect germanium crystals arranged in the parallel position. Multiple diffraction from these crystals produces a monochromated X-ray beam which can be several millimeters wide while still exhibiting extremely high angular resolution. As a result, effective sample volumes can be employed with maximum volume-to-thickness ratios. The principal features of the instrument are discussed with emphasis on the advantages of this device over those employing complex slit systems and film-re cording techniques, Data are presented to illustrate the operation, intensity, and resolution of the unit.

Small-Angle X-ray Scattering of Polymers

“…There have been considerable interests in further development of the Bonse−Hart instrument, − particularly in synchrotron X-ray facilities, because of its potential applications to many current topics in materials research with length scales in the mesoscopic micrometer-size range. It should also be noted that many materials studies deal with high temperatures and involve temperature scanning, jumping, quenching, and annealing experiments.…”