Thermal conductivity and heat capacity of solid NaCl and NaI under pressure

• We measured the thermal conductivity and heat capacity per unit volume for solid NaCl and NaI using the transient hot-wire technique. Measurements were performed in the temperature range 100–400 K and at pressures up to 2 GPa. Analysis of the thermal conductivity data showed that the Leibfried-Schlömann formula is a better description for NaCl than for NaI. For both NaCl and NaI the effect of optic phonons on thermal conductivity cannot be ignored. However, taking only acoustic phonons into account is a better approximation for NaI than for NaCl, due to the larger ionic mass ratio for NaI. The specific heat capacities, obtained at room temperature, were approximately independent of pressure.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

Thermal conductivity

heat capacity

specific heat

high pressure

alkali halides

NaCl

NaI

Publication and Content Type

ref (subject category)

art (subject category)