Applications of. gamma. -ray diffractometry

Journal Article · Tue Dec 01 00:00:00 EST 1981 · Nucl. Sci. Appl., Sec. A; (United States)

OSTI ID:6588277

Schneider, J R ^[1]

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1. Hahn-Meitner-Institut fuer Kernforschung Berlin G.m.b.H. (Germany, F.R.)

In a number of solid state diffraction experiments it is an advantage to replace the commonly used X-ray or neutron beams by ..gamma..-radiation, e.g. 412 keV ..gamma..-radiation of radioactive gold. The absorption of this radiation in matter is very weak and mainly due to Compton scattering (the mean free path being approximately 1 cm in copper). Therefore large single crystals can be studied which may be contained in any cryostat, oven or high pressure device (no window problem). In many cases the diffraction process can be described within the first order Born approximation, remaining extinction corrections are small. Each individual ..gamma..-ray rocking curve is measured on an absolute scale. The Bragg angles are small (of the order of 1) and thus the shape of the measured ..gamma..-ray rocking curves is affected mainly by lattice tilts. The technique was widely applied to study the mosaic structure of large 'as grown' single crystals and of samples or monochromators for neutron scattering experiments. Structural phase transitions where strain is an order parameter often show twinning patterns strongly dependent of the temperature which can be studied in a straight forward by means of ..gamma..-ray diffractometry. The measurement of absolute structure factors in imperfect single crystals as an experimental check of the theoretical ground state wave functions is presented in some detail.

• OSTI ID: 6588277
• Journal Information: Nucl. Sci. Appl., Sec. A; (United States), Vol. 1:3
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
GAMMA DIFFRACTOMETERS
USES
GAMMA RADIATION
DIFFRACTION
ALUMINIUM
BIBLIOGRAPHIES
BRAGG REFLECTION
COPPER
CRYSTAL STRUCTURE
GOLD
GROUND STATES
KEV RANGE 100-1000
MONOCHROMATORS
MONOCRYSTALS
NEUTRON BEAMS
NIOBIUM
REVIEWS
STRUCTURE FACTORS
WAVE FUNCTIONS
BEAMS
COHERENT SCATTERING
CRYSTALS
DIFFRACTOMETERS
DOCUMENT TYPES
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY LEVELS
ENERGY RANGE
FUNCTIONS
IONIZING RADIATIONS
KEV RANGE
MEASURING INSTRUMENTS
METALS
NUCLEON BEAMS
PARTICLE BEAMS
RADIATIONS
REFLECTION
SCATTERING
TRANSITION ELEMENTS
440101* - Radiation Instrumentation- General Detectors or Monitors & Radiometric Instruments