THE BEHAVIOUR OF RECOIL ATOMS IN IONIC SOLIDS

Journal Article · Tue Feb 19 04:00:00 EST 1963 · Proc. Roy. Soc. (London), Ser. A

DOI:https://doi.org/10.1098/rspa.1963.0038· OSTI ID:4749701

Anderson, J S; Bevan, D J.M.; Burden, J P

The rate of escape of Rn/sup 220/ from solids containing radiothorium depends upon both recoil and diffusion and is steady at any temperature if the distribution of radioactive material remains unchanged. At very high temperatures the emanating power of ThO/sub 2/ (and other oxides) increases with time at constant temperature; the emanating powertemperature characteristics eventually resemble those of a solid with a surface source of thoron. The enhancement of emanating power decays with time in such a way as to prove that Ra/ sup 224/ is no longer uniformly distributed, although the distribution of the parent Th/sup 228/ is unchanged; the Ra/sup 224/ atoms, formed by recoil from Th/ sup 228/, migrate during their lifetime to trapping sites which, in this case, are on the surface. Similar effects are found with BaThO/sub 3/ and BaF/sub 2/, even though Ra/sup 224/ can replace Ba isomorphously; these compounds are anionic conductors and have only a low concentration of vacant cation sites at high temperatures. If (e.g., in BaO) vacant sites capable of accepting large cations are present in high concentration, the recoil atoms are trapped and retained in uniform distribution. (auth)

• Research Organization: National Chemical Lab., Teddington, Middx, Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-014275
• OSTI ID: 4749701
• Journal Information: Proc. Roy. Soc. (London), Ser. A, Journal Name: Proc. Roy. Soc. (London), Ser. A Vol. Vol: 272
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ATOMS
BARIUM FLUORIDES
BARIUM OXIDES
CHEMISTRY
DIFFUSION
DISTRIBUTION
EFFICIENCY
EVAPORATION
HIGH TEMPERATURE
IONS
LIFETIME
POWER
RADIUM 224
RADON 220
RECOILS
SOLIDS
SURFACES
THORIUM 228
THORIUM OXIDES