Tracking and understanding the first-order structural transition in Er5Si4Physical Review B
Publication VersionPublished Version
AbstractTemperature-dependent single crystal x-ray-diffraction studies revealed a reversible first-order phase transition in Er5Si4. The high-temperature phase adopts the orthorhombic Gd5Si4-type structure, and the low-temperature phase has the monoclinic Gd5Si2Ge2-type structure. Unlike the magnetic/martensitic transition in Gd5Si2Ge2, the structural change in Er5Si4 is not coupled with a magnetic transition, and the structural sequence below room temperature is just the reverse. A vibrational mode that breaks half of the interslab silicon dimers and rotates slabs in the monoclinic structure, thus lowering the symmetry from Pnma to P1121/a, has been identified using Landau theory. While the monoclinic phase is electronically stabilized at low temperatures, the orthorhombic phase is entropically preferable at high temperatures.
Copyright OwnerAmerican Physical Society
Citation InformationYurij Mozharivskyj, Alexandra O. Pecharsky, Vitalij K. Pecharsky, Gordon J. Miller, et al.. "Tracking and understanding the first-order structural transition in Er5Si4" Physical Review B Vol. 69 Iss. 144102 (2004) p. 1 - 13
Available at: http://works.bepress.com/gordon-miller/110/