A mass spectrometric study of the molecular and ionic sublimation of lanthanum tribromide

作者：Butman M F^*; Motalov V B; Kudin L S; Grishin A E; Kryuchkov A S; Kraemer K W

来源：Russian Journal of Physical Chemistry, 2008, 82(2): 164-171.

DOI：10.1134/S0036024408020040

The molecular and ionic composition of vapor over lanthanum tribromide was studied by high-temperature mass spectrometry under the conditions of sublimation from a Knudsen effusion cell and from an open single crystal surface. The partial pressures of LaBr3 and La2Br6 in saturated vapor and the ratio between their sublimation coefficients under free vaporization conditions were determined. The second and third laws of thermodynamics were used to calculate the enthalpies of sublimation of LaBr3 in the form of monomers and dimers. In ionic sublimation studies, the emission of the Br (-), LaBr4-, and La2Br7- negative ions was recorded in both regimes. Studies of the ionic sublimation of LnX(3) single crystals were shown to give reliable data on the thermochemical properties of negative ions.

• 出版日期2008-2
• 单位北京化工大学