104
A. Palenzona et al. / Journal of Alloys and Compounds 348 (2003) 100–104
showed, among the strong lines of Yb5Si3, seven reflec-
tions which could be indexed with an orthorhombic cell
pertaining to the anti-PbCl2 structure type whose lattice
constant values (Table 1) could support the existence of
Yb2Si. No other indications of its existence, however,
could be thereafter obtained; this question therefore is still
open and further work is needed to solve it.
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1. Determination of the thermochemical properties of the
intermediate phases by means of vapor pressure mea-
surements over the various biphasic regions. The en-
thalpy changes for the high temperature decomposition
reactions have been determined and the heat of forma-
tion of the intermediate Yb–Si phases derived therein.
The results so far obtained will be reported separately
[25]. Some results have been anticipated here.
2. An investigation concerning the determination of the
physical properties of the Yb–Si compounds in a wide
temperature range (specific heat, magnetic suscep-
tibility, electrical resistivity) [26].
[24] P. Manfrinetti, M.L. Fornasini, A. Palenzona, Intermetallics 8 (2000)
223.
Acknowledgements
[25] G. Balducci, S. Brutti, P. Manfrinetti, A. Palenzona, to be presented
at the International Conference ‘Thermodynamics of Alloys’ TOFA-
2002, Italy.
[26] S.K. Dhar, P. Manfrinetti, A. Palenzona, P. Bonville, to be presented
at the International Conference ‘Strongly Correlated Electron Sys-
tems’ SCES-2002, Poland.
The authors thank the Italian Ministero dell’Istruzione,
`
dell’Universita e della Ricerca (MIUR) for financial sup-
port, under the National Research Program ‘Alloys and
intermetallic compounds: thermodynamics, physical prop-
erties, reactivity’. The support by the Consiglio Nazionale
delle Ricerche (CNR), under ‘Progetto finalizzato-
Materiali speciali per tecnologie avanzate II’, is also
acknowledged.