NUCLEAR MAGNETIC RESONANCE OF H$sup 1$ AND Nb$sup 93$ IN THE NIOBIUM- HYDROGEN SYSTEM

Journal Article · Fri May 01 04:00:00 EDT 1964 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.134.A666· OSTI ID:4036371

Zamir, D; Cotts, R M

The nuclear magnetic resonance of H and /sup 93/Nb were observed in the NbH/sub x/ system as a function of hydrogen concentration and temperature. It is shown that line narrowing of the steady-state absorption resonance is limited at high temperatures by inhomogeneous broadening due to a distribution of fields caused by bulk paramagnetism of the samples. A sharp, though not discontinuous, change of hydrogen diffusion is observed at temperatures that range from 60 to 100 deg C and that depend on hydrogen concentration. Niobium resonance linewidth and intensity changes indicate that sharp change in proton diffusion is associated with the phase transition to the high-temperature cubic phase of the hydrides. The activation energy of NbH/sub 0.7/ is E/sub a/ = 5 kcal/mole in the low-temperature (orthorhombic) phase and E/sub a/ = 3.7 kcal/mole in the high- temperature (cubic) phase. The niobium resonance is observable at all hydrogen concentrations. As the hydrogen concentration increases, the Nb Knight shift decreases. The fractional change in shift is DELTA K/K = -9% at NbH/sub 0.7/. (auth)

• Research Organization: Cornell Univ., Ithaca, N.Y.
• NSA Number: NSA-18-017811
• OSTI ID: 4036371
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 134; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CHEMISTRY
CONFIGURATION
DIAGRAMS
DIFFUSION
DISTRIBUTION
ENERGY LEVELS
EXCITATION
FIELD THEORY
HIGH TEMPERATURE
HYDROGEN
LATTICES
LOW TEMPERATURE
MAGNETIC FIELDS
MAGNETISM
MEASURED VALUES
MIXING
MOLECULES
NIOBIUM 93
NIOBIUM HYDRIDES
NUCLEAR MAGNETIC RESONANCE
PARAMAGNETISM
PHASE DIAGRAMS
PROTONS
QUANTITY RATIO
SPECTRAL SHIFT
TABLES
TEMPERATURE
VARIATIONS