Superconductivity and the structural phase transitions in palladium hydride and palladium deuteride

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1980

DOI:https://doi.org/10.2172/5272299· OSTI ID:5272299

Standley, Robert Wendell ^[1]

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1. Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Physics

The results of two experimental studies of the superconducting transition temperature, T_c, of palladium hydride, PdH_x, and palladium deuteride, PdD_x, are presented. In the first study, the superconducting transition temperature of PdH_x(D_x) is studied as a function of H(D) concentration, x, in the temperature range from 0.2 K to 4K. The data join smoothly with those reported previously by Miller and Satterthwaite at higher temperatures, and the composite data are described by the empirical relation T_c = 150.8 (x-x_o) ^2.244, where x_o = 0.715 for hydride samples and 0.668 for deuteride samples. The results, when compared with the theoretical predictions of Klein and Papaconstantopoulos, et al., raise questions about the validity of their explanation of the reverse isotope effect, which is based solely on a difference in force constants. In the second study, the effect of the order-disorder structural transition associated with the 50 K anomaly on the superconductivity of PdH_x(D_x) is investigated. Samples were quenched to low temperatures in the disordered state, and their transition temperatures measured. The samples were then annealed just below the anomaly temperature, and the ordering process followed by monitoring the change in sample resistance. The transition temperatures in the ordered state were then measured.

• Research Organization: Illinois Univ., Urbana (United States). Dept. of Physics
• Sponsoring Organization: USDOE; National Science Foundation (NSF)
• DOE Contract Number: AC02-76ER01198; EY-76-C-02-1198
• OSTI ID: 5272299
• Report Number(s): DOE/ER/01198--1315
• Country of Publication: United States
• Language: English

Related Subjects

656102* -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DATA
DEUTERIUM COMPOUNDS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
INTERSTITIALS
NUMERICAL DATA
PALLADIUM COMPOUNDS
PALLADIUM HYDRIDES
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
POINT DEFECTS
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE