Abstract
Neutron scattering and AC susceptibility measurement have been made on isotopically enriched (SmMn2)-Sm-154(Ge0.9Si0.1)(2). A temperature versus pressure magnet:ic phase diagram is proposed. The incommensurate cone structures detected in SmMn2Ge2 at low temperatures and pressures do not appear in the phase diagram of the Si-substituted system. There is no evidence of a change in the magnetic structure associated with a small peak in susceptibility observed at around 145 K which has previously been interpreted in terms of changes to the cone structure. However, as with SmMn2Ge2, the non-collinear magnetic structures of these magnetic phases are such that a larger antiferromagnetic component appears within (001) ab-planes in the ferromagnetic states than in the antiferromagnetic state. With increasing Si substitution, the antiferromagnetic phase becomes the magnetic equilibrium state over a wider temperature range. The observed changes in the Mn-Mn spacing and magnetic coupling are largely consistent with previous related observations, although under a pressure of similar to 8 kbar, low-temperature magnetic structures are found below the critical lattice spacing of a = 4.031 Angstrom which are similar to those observed at ambient pressure. (C) 2000 Elsevier Science B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 317-323 |
Number of pages | 7 |
Journal | Physica B : Condensed Matter |
Volume | 291 |
Issue number | 3-4 |
DOIs | |
Publication status | Published - Sept 2000 |
Keywords
- magnetic structure
- neutron diffraction
- AC susceptibilty
- SmMn2Ge2
- SMMN2GE2
- SMMN2(GE1-XSIX)(2)
- NDMN2GE2