EFFECT OF ISOTOPIC COMPOSITION ON ELECTRICAL RESISTANCE OF LITHIUM

Technical Report · Sun Jan 01 04:00:00 EST 1961

OSTI ID:4836576

Leffler, R G; Montgomery, D J

The electrical resistance of solid metallic Li containing varying proportions of Li/sup 6/ and Li/sup 7/ was measured between 4.2 and 295 deg K. For the isotopically-pure substances, the main features of the behavior agree with the predictions of the Bloch-Gruneisen law, the characteristic temperature being inversely proportional to the square root of the mass. The deviation in the details is just that found for most other metals. For the isotopically- impure substances, the behavior of the resistance as a function of temperature can be described just as that of an isotopically-pure substance with a mass dependent on the isotopic composition. From the present data the arithmetic-mean cannot be preferred over the harmonic-mean isotopic mass, and a basis for decision between certain theoretical proposals concerned with the effect of isotopic impurities on lattice-vibration spectra is not obtained. It appears definite that no need exists to invoke a scattering mechanism that looks upon isotopes as introducing imperfections in the lattice; rather, their presence merely modifies the lattice-vibration spectrum. The effect of the martensitic transition at low temperatures is barely discernible. (auth)

• Research Organization: Michigan State Univ., East Lansing
• NSA Number: NSA-16-000590
• OSTI ID: 4836576
• Report Number(s): TID-14098
• Country of Publication: United States
• Language: English

Related Subjects

BLOCH THEORY
DEFECTS
ELECTRIC CONDUCTIVITY
ELECTRONS
IMPURITIES
ISOTOPE EFFECTS
LATTICES
LITHIUM
LITHIUM 6
LITHIUM 7
LOW TEMPERATURE
MARTENSITE
MASS
MEASURED VALUES
METALS
PHASE DIAGRAMS
PHYSICS
QUANTITY RATIO
QUANTUM MECHANICS
SCATTERING
SOLIDS
SPECTRA
TEMPERATURE
VIBRATIONS