PARTIAL PRESSURES OF HG(G) AND TE2(G) IN HG-TE SYSTEM FROM OPTICAL DENSITIES,

Abstract

The partial pressures of Hg(g) and Te2(g) in equilibrium with Hg-saturated HgTe(c), Te-saturated HgTe(c), and some Hg-Te melts between about 400 and 700C were determined by measuring the optical density of the coexistent vapor as a function of wavelength. In agreement with mass spectrographic data, no evidence was obtained for HgTe(g) molecules. The partial pressures of the elements depend strongly on the composition of the solid phase. The maximum value of pHg in equilibrium with HgTe(c) is 19 atm, the pressure over Hg-saturated HgTe(c) between 643 and 656C. At 670C, the maximum melting point, pHg = 12.5 atm. At any temperature Hg(g) is the predominant vapor species over HgTe(c) of any composition. Liquidus temperatures for compositions between 31 and 58.5 at. %Te have been obtained from the partial pressure data, which also show that at 488C Hg-saturated HgTe(c) contains 49.9=0.2 at.% Te and Te-saturated HgTe (c) contains less than 50.5 at.% Te. The Gibbs free energy of formation of HgTe(c) from Hg(g) and Te2(g), which is practically independent of the composition of the solid phase, is found to be -41.66+42.71 (0.001) T kcal/mole. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 24, 1964
Accession Number
AD0620980

Entities

People

  • A. J. Strauss
  • R. F. Brebrick

Organizations

  • Massachusetts Institute of Technology

Tags

DTIC Thesaurus Topics

  • Agreements
  • Chemistry
  • Energy
  • Free Energy
  • Melting
  • Melting Point
  • Molecules
  • Partial Pressure
  • Phase
  • Solid Phases

Fields of Study

  • Materials science

Readers

  • Marine Propulsion Engineering and Naval Architecture
  • Materials Science and Engineering.