Moessbauer spectroscopy at pressures up to 40 GPa

Conference · Wed Nov 20 04:00:00 EST 1991

OSTI ID:10113801

Taylor, R D ^[1]; Pasternak, M P ^[2]

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1. Los Alamos National Lab., NM (United States)
2. Tel Aviv Univ. (Israel)

Mossbauer spectroscopy (MS) is a viable ``non-contact`` technique applicable to high-pressure, diamond anvil cells (DAC) with samples containing a wide variety of the elements suitable for MS. The convenience and simplicity of diamond anvil cells as a means to obtain static high pressures even into the megabar regime has resulted in a renewed interest in pressure as a complement to the usual physical measurements. However, the required small sample size and the difficulty of communicating with the sample leave only x-ray and optical spectroscopy as the readily available tools. Mossbauer spectroscopy which involves recoil-free, low-energy {gamma} rays, provides a powerful additional technique to study a myriad of physical properties in a DAC. MS concerns a particular isotope and can provide local information on phase changes and hysteresis, isomer shifts, valence, bonding, magnetic and quadrupolar interactions, lattice dynamics, and multiple sites. The Mossbauer effect has been seen in about a hundred isotopic transitions in about forty different elements; many are suitable for DAC-MS, most notably {sup 57}Fe, {sup 119}Sn, {sup 121}Sb, {sup 125}Te, {sup 129}I, {sup 149}Sn, {sup 151}Eu, {sup 161}Dy, {sup 1976}Au, and {sup 237}Np. Since the information available from MS is obtained from analyzing the precise energy profile of the Mossbauer {gamma} ray from a source/absorber combination, no contacts or difficult coupling to the DAC are required. We review a number of salient features of the DAC-MS method and present some examples, including new work on FeI{sub 2}.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 10113801
• Report Number(s): LA-UR--91-3912; CONF-9111166--1; ON: DE92005072
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102
DIAMONDS
HYSTERESIS
IRON
METALS
MOESSBAUER EFFECT
MOESSBAUER SPECTROMETERS
PHASE TRANSFORMATIONS
PRESSURE EFFECTS
STRUCTURE AND PHASE STUDIES
VALENCE
VERY HIGH PRESSURE