Thermochemistry of some binary alloys of silver with the lanthanide metals by high temperature direct synthesis calorimetry
作者:S.V Meschel、O.J Kleppa
DOI:10.1016/j.jallcom.2003.11.160
日期:2004.8
The standard enthalpies of formation of some lanthanide silver compounds have been measured by high temperature direct synthesis calorimetry at 1373 +/- 2 K. The following results (in kJ/mol of atoms) are reported: 1: 1 composition-AgTb (-36.5 +/- 2.9); AgDy (-37.3 +/- 1.8); AgEr (-44.9 +/- 3.2); AgTm (-43.0 +/- 2.3); 2:1 composition-Ag2Pr (-24.7 +/- 1 1.6); Ag2Nd (-21.8 +/- 1.9); Ag2Gd (-23.9 +/- 1.6); Ag2Tb (-22.7 +/- 1.8); Ag2Dy (-22.3 +/- 2.3); Ag2Ho (-25.0 +/- 2.3); Ag2Er (-24.0 +/- 2.3); Ag2Tm (-24 +/- 3); Ag2Lu (-25.6 +/- 1.9); 3:1 composition-Ag3Tb (-20.6 +/- 2.0); Ag3Dy (-22.8 +/- 1.9); Ag3Ho (-25.1 +/- 2.0); Ag3Er (-25.4 +/- 2.3); Ag3Tm (-20.2 +/- 2.3). The results are compared with the semi-empirical predicted values of Miedema and coworkers and with the values predicted by Gschneidner for lanthanide alloys. They are also compared with the enthalpies of formation of the Au-LA systems by the present authors. (C) 2003 Elsevier B.V. All rights reserved.