Community Research and Development Information Service - CORDIS


The compressibility of manganese compounds with different structure and composition (Ymn(2),Y(6)Mn(23),Ymn(12), Y(Mn(0.80Fe(0.2))2 was studied up to ~40 Gpa using a diamond anvil cell with synchrotron radiation.
In the case of Ymn(2) we observed a very large compressibility (Ko = 19.0 Gpa Ko = 15.2) which decreased considerably when changing the atomic surrounding of the Mn atoms, as shown by the pseudobinary compound Y(Mn(0.8)Fe(0.2) )2 (Ko=47.1 Gpa, Ko=13.2) and ScMn(2) (Ko=80.1 Gpa Ko=9.04). The other two Y-Mn compounds Y(6)Mn(23) (Ko=39.2 Gpa Ko=15.8) and Ymn(12) (Ko=83.7 Gpa and Ko=13.5) also show an enhanced compressibility, however not as large as in Ymn(2).
Thermal expansion data, which were also included in the discussion, show that the thermal expansion is closely related to the compressibility. The unusually large differences in the compressibility and the thermal expansion among the investigated compounds have been attributed to a different ' chemical pressure' acting on the Mn atoms, depending on the space available on the Mn-sites in the different structures. .

Additional information

Authors: LINDBAUM A, University of Vienna, Vienna (AT);GRATZ E, University of Vienna, Vienna (AT);HEATHMAN S, Institute for Transuranium Elements, Karlsruhe (DE);MERESSE Y, Institute for Transuranium Elements, Karlsruhe (DE)
Bibliographic Reference: Article:Journal of Physics Condensed Matter, 1998
Record Number: 199910265 / Last updated on: 1999-03-12
Original language: en
Available languages: en