Magnetic and Thermodynamic Studies on GdNiAl3
Nallamuthu S1, Arun K1, T.P.Rashid1, Nagalakshmi R 1*,
1
Department of Physics, National Institute of Technology, Tiruchirappalli 620 0015, India
*E-mail for corresponding author: nagaphys@yahoo.com Tel.: 04312503615
Abstract
We report on a comprehensive study of the heat capacity, and
magnetization studies on the polycrystalline
GdNiAl3
synthesized by arc melting under a purified argon atmosphere.
The GdNiAl3 forms with the orthorhombic (space group
Pnma) YNiAl3-type structure.
GdNiAl3 we observed three anomalies at T=64K, 72K
and 165K respectively. The peak at T=72K was
insensitive to magnetic field. Further analyses we are
waiting for another measurement and all the result will
be discussed later
Introduction
In rare earth bearing intermetallic compounds, Gd
members give the clearest indication of the strength and
sign of the magnetic interaction, without any
complications associated with crystalline electric field
splitting of the Hund’s rule ground state multiplet. In
view of this, it is somewhat surprising that GdNiAl3. A
large number of ternary compounds have been reported
in the R–Ni–Al systems, where R is a rare earth metal.
They are characterized by 17 different structure types of
invariable compositions and complete ordering of the
atoms in these structures has been reported[1]. To the
best of our knowledge there have been no physical
property measurements on this compound. Hence this
motivated us to report the magnetic and heat capacity
measurements.
Fig.1. Magnetic susceptibility and (χ)inverse of
susceptibility (χ−1) as a function of temperature
measured with H=100 Oe of GdNiAl3
Experimental
Samples of nominal composition GdNiAl3 were
synthesized from the elements high purity of Gd, Ni and
Al by arc melting in a water-cooled copper crucible
with a tungsten electrode under a purified argon
atmosphere. The phase analysis was performed based on
X-ray powder diffraction data and the investigation of
the microprobe analysis confirms their chemical
homogeneity from SEM-EDX.
Results
The temperature dependent magnetic susceptibility χ(T)
= M/H and inverse magnetic susceptibility (1/χ(T)) at H
= 100 Oe of GdNiAl3 are shown in Fig.1. The magnetic
susceptibility shows a peak at T N = 165 K as an
indicative of ferromagnetic ordering of Gd moments.
The high temperature magnetic susceptibility was fitted
to a Curie–Weiss law. The fitting parameters estimated
are θp = 35.9 K and μeff = 7.77 μB/Gd3+. The
temperature dependence of the specific heat Cp has
measured from 50-300K up to 3T. In specific heat of
Conclusion
We have measured the specific heat,
magnetization of the GdNiAl3 All measurements shows
interesting low temperature behavior. Further results
will be discussed in detail during the presentation in the
conference.
Acknowledgment
The authors (R.N) thank Department of Atomic Energy
(DAE), Board of Research in Nuclear Sciences (BRNS)
Govt. of India for supporting this work under DAE
Young
Scientists
Research
Award
(No:
2010/20/37P/BRNS/2513).
Reference
[1]. Svitlana Pukas, Oksana Matselko, Roman
Gladyshevskii, Chem. Met. Alloys 3, 35-41(2010)