A 41 KILOBARS TRANSITION IN YTTERBIUM
During a study on the effect of pressure on the electrical resistance of ytterbium, the transition pressure at room temperature was observed at 40 plus or minus 2 kbars or 41 plus or minus 2 kbars based on a bismuth 6--8 transition at 88 and 91 kbars, respectively. Ytterbium metal of 99.9% purity was extruded into wires of 0.003 in. dia., annealed at 400 deg C and bent into a circular arc, the center coinciding with the axis of the anvils. This procedure minimizes the pressure gradient in the system. The wire was mounted between AgCl discs in 1/2 in. Bridgman anvils. The resistance of the sample was determined by measuring the emf drop across the sample while a known fixed current was passed through the system. The resistance changed by a factor of approximates 14 in. going from the alpha to BETA phase. Although the transition was quite slow, no difficulty was experienced in locating the pressure at which the transition starts due to the change in sign of the pressure coefficient. A large hysteresis exists in the-pressure-resistance behavior on decompression. (H.G.G.)
- Research Organization:
- California. Univ., Berkeley. Dept. of Chemistry and California. Univ., Berkeley. Lawrence Radiation Lab.
- DOE Contract Number:
- W-7405-ENG-48
- NSA Number:
- NSA-17-016662
- OSTI ID:
- 4752723
- Report Number(s):
- UCRL-10332
- Country of Publication:
- United States
- Language:
- English
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