Magnetic phase transitions in intermetallic NdAgSi compound


Oner Y. , ROSS J., SOLOGUB O., SALAMAKHA P.

JOURNAL OF ALLOYS AND COMPOUNDS, cilt.415, ss.38-42, 2006 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 415
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1016/j.jallcom.2005.07.049
  • Dergi Adı: JOURNAL OF ALLOYS AND COMPOUNDS
  • Sayfa Sayıları: ss.38-42

Özet

Electrical resistivity and magnetization measurements have been carried out on the intermetallic NdAgSi compound in the temperature range of 5-300 K in magnetic fields up to 55 kOe. The low-field dc magnetic susceptibility (X = M/H) gives a sharp increase at about T = 44 K and splits into two branches at lower temperatures in magnetic fields up to I kOe for zero-field-cooled (ZFC) and field-cooled (FC) cases. At higher temperatures, it exhibits a typical paramagnetic Curie-Weiss behavior with the effective magnetic moment of approximately 22 mu(B)/f.u. The ZFC-branch for H = 10 Oe gives an another anomaly at about T = I I K being in agreement with the ac susceptibility data. Both anomalies were also observed in the resistivity. The resistivity decreases linearly with decreasing temperature (metallic behavior) and changes its slope first sharply at T = 44 K and then slightly at T = I I K. Furthermore, the technical saturation magnetic moment per formula (f.u.) at T = 5 K was estimated to be 2.7 mu(B)/f.U.. This value is larger by at least 0.5 mu(B)/f.u. than that obtained at temperatures above T = 44 K. This enhancement of the magnetic moments at neodymium atom sites may also responsible for the anomaly observed at 44 K for both susceptibility and resistivity data. The slightly increment in magnetic moment may be attributed to the splitting of ground levels of Nd atoms due to the exchange interaction between the 4f electron from neodymium (Nd) atom and the 3p conduction band electron spins of silicon (Si) atoms enhanced by Coulomb interactions. (c) 2005 Elsevier B.V. All rights reserved.