Structural and magnetic properties of Ho-5(SixGe1-x)(4)

• Type: Article in International Scientific Journal
• Date: 2008

Authors

pereira, a. m. (Author) Other; sousa, j. b. (Author) FCUP; araujo, j. p. (Author) FCUP; magen, c. (Author) Other; algarabel, p. a. (Author) Other; morellon, l. (Author) Other; marquina, c. (Author) Other; ibarra, m. r. (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: PHYSICAL REVIEW B

Vol. 77

ISSN: 2469-9950

Indexing

ISI Web of Knowledge - 18 Citations

Scopus - 22 Citations

Other information

Authenticus ID: P-004-0PH

DOI: 10.1103/physrevb.77.134404

Abstract (EN): The crystal structure, phase relationship, and magnetic properties of the system Ho(5)(Si(x)Ge(1-x))(4) have been studied using polycrystalline samples with compositions x=0, 0.25, 0.5, 0.75, 0.875, and 1. At room temperature, the concentration range 0 <= x <= 0.5 presents an orthorhombic Sm(5)Ge(4)-type O(II) structure, whereas the monoclinic M phase sets in the compounds with concentrations x=0.75 and 0.875. The orthorhombic Gd(5)Si(4)-type O(I) structure is present only for x=1. Magnetic characterization has shown that the Ho(5)(Si(x)Ge(1-x))(4) system is paramagnetic at 300 K. The samples with an O(II) structure undergo a second order antiferromagnetic transition with T(N) between 25 and 30 K. The compounds with x > 0.5 present a low temperature ferromagnetic phase with T(C) rapidly increasing with Si content (dT(C)/dx=95 K). A second magnetic transition has been detected in the whole composition range at T(SR)similar to 15 K, which might correspond to a reorientation of the easy magnetization axis. Linear thermal expansion experiments evidence no spontaneous structural transition with the exception of Ho(5)Ge(4), where a small anomaly has been observed, which is probably due to the structural change of a small fraction of the sample volume.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7