Density and Expansivity of Solid Argon

Vacancies in Solid Argon

The enthalpy and entropy of vacancy creation in solid argon are re-evaluated using the two-body force approximation. At the triple point, the resulting vacancy free energy is g, = 1900 -4.0 RTcaljmole vat. This does not agree well with previous calculations of g,, but agrees well with experimental values of g, obtained from the argon specific heat”’ C, (but not with the questionable values obta...

Self-Diffusion in Solid Argon

The self-ditlusion coefficient D = De exp( —() /RT) for solid argon has been measured in thin specimens of large grain size by a tracer technique. The results, Dp=0.2+p. 14 '3~ cm~ sec ' and Q =3600+150 cal mole ', are lower than those obtained in previous investigations. The value of Q agrees reasonably well with a twobody absolute-rate calculation for vacancy migration, but not with calculati...

Phonons in solid argon monolayers.

Department ofPhysics and Astronomy, University ofDelaware, Newark, Delaware 19716 (Received 21 June 1989) Inelastic neutron scattering studies of excitations in ' Ar solid monolayers show a large thermal broadening of the scattered intensity between T =4 and 45 K. %'e find this thermal broadening can be readily explained in terms of anharmonic interactions between the phonons in the monolayers....

Formation and characterization of HUF and DUF in solid argon.

Reactions of laser-ablated U atoms with HF and DF in condensing and solid rare gas produce HUF and DUF as the major new products based on close agreement between observed and calculated vibrational frequencies and deuterium shifts for U-H and U-F stretching modes at 1383 and 544 cm(-1), respectively.

Ground- and excited-state properties of solid argon under pressure