Abstract
Cubic Sm4Bi3 undergoes a first-order transition into a rhombohedral phase at about 260 K. This change has been ascribed to a charge-ordering transition from the thermal valence fluctuating state into a static mixture of di- and trivalent sites. In order to determine the positions of the Sm2+ and Sm3+ ions below the transition temperature, we have investigated a Sm4Bi3 single crystal by polarized neutron diffraction. A uniaxial pressure was applied along the [1 1 1] direction to avoid the formation of domains. The rhombohedral nuclear structure was first refined using unpolarized neutron measurements. From the flipping ratios measured with polarized neutrons at T = 6 K in a magnetic field of 4.6 T applied along the [1̄ 0 1] rhombohedral direction, the two Sm sites were found to have different magnetic characters: SmI, along the compressed diagonal of the cube, carries a moment of 0.017(5)μB with a Sm3+ form factor, whereas SmII, along the other diagonals, carries a moment of 0.063(5)μB with a Sm2+ form factor.
Original language | English |
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Pages (from-to) | 47-50 |
Number of pages | 4 |
Journal | Physica B: Condensed Matter |
Volume | 267-268 |
DOIs | |
Publication status | Published - 1999 Jun |
Externally published | Yes |
Event | Proceedings of the 1998 2nd International Workshop on Polarised Neutrons for Condensed Matter Investigations, PNCMI '98 - Grenoble Duration: 1998 Sep 21 → 1998 Sep 23 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering