Lanthanum Dilution Effects on the Giant Magnetocaloric Gd5Si1.8Ge2.2 Compound

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Andrade, VM (Author) Other; Belo, JH (Author) Other; Reis, MS (Author) Other; Costa, RM (Author) Other; pereira, a. m. (Author) FCUP; araujo, j. p. (Author) FCUP

Journal

Title: Physica Status Solidi (B): Basic Research

Vol. 255

ISSN: 0370-1972

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 4 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-00P-M6Q

DOI: 10.1002/pssb.201800101

Abstract (EN): A study on the fundamental properties of Gd5-xLaxSi1.8Ge2.2 pseudo-binary compounds with x=1, 2, 3, 4, and 5 is performed by means of X-ray powder diffraction (XRD) and magnetic measurements. An evolution from a monoclinic (M) Gd5Si2Ge2-type to a tetragonal (T) Zr5Si4-type structure, with the addition of La, is observed, finding that the T phase is stable for x2. A monotonic expansion of the unit cell volume with a rate of 28 angstrom(3)/La by increasing the content of the non-magnetic La ions in the system influences significantly the overall magnetic behavior. For instance, T-C decreases in a rate of dT(C)/dx=-47.8KLa(-1); and a considerable hysteresis reduction is observed as a result of the change on the nature of the phase transition from a first to a second-order one. Hence, these results reveal the impact of a non-magnetic La substitution on both magnetic and crystallographic properties of this series.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6