Synthesis, Structure and Magnetism of ErCoIn 5
- PDF / 297,529 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 52 Downloads / 188 Views
FF3.7.1
Synthesis, Structure and Magnetism of ErCoIn5 Evan Lyle Thomas,† Erin E. Erickson,† Monica Moldovan,‡ David P. Young,‡ and Julia Y. Chan*,† †
Department of Chemistry, Louisiana State University, 232 Choppin Hall, Baton Rouge, LA 70803, USA ‡ Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA
Keywords: LaCoIn5, ErCoIn5, LnCoIn5, Electrical resistivity, Single crystal, X-ray diffraction, Magnetoresistance *
To whom correspondence should be addressed E-mail: [email protected] Telephone: (225) 578-2695 Fax: (225) 578-3458
Abstract A new member of the LnMIn5 family, ErCoIn5, has been synthesized by a flux-growth method. The structure of ErCoIn5 was determined by single crystal X-ray diffraction. It crystallizes in the tetragonal space group P4/mmm, Z = 1, with lattice parameters a = 4.5400(4) and c = 7.3970(7) Å, and V = 152.46(2) Å3. Electrical resistivity data show metallic behavior. Magnetic susceptibility measurements show this compound to be antiferromagnetic with TN = 5.1 K. We compare these experimental results with those of LaCoIn5 in an effort to better understand the effect of the structural trends observed on the transport and magnetic properties. Introduction Rare-earth elements possess 4f and 5f electrons which may hybridize with the d conduction electrons of transition metals. This interaction leads to the interesting physical properties observed in intermetallic compounds: intermediate valence, superconductivity, and/or heavy-fermion behavior, where Kondo interactions lead to large effective masses 102 times larger than that of a free electron. Some compounds exhibit both superconductivity and heavy-fermion behavior – a phenomenon considered to be unconventional – where the magnetic moments of the f-electrons are strongly coupled to the conduction d-electrons.1 This type of behavior is observed in several U-2-7 and Ce8-containing heavy-fermions. The CeMIn5 (M = Co, Rh, Ir) compounds have recently attracted much attention.9-11 The Co- and Ir-analogues are both superconducting at 2.3 K and 0.4 K, respectively, under ambient pressure.9, 10 The Rh-analogue however, orders antiferromagnetically at 3.8 K in ambient pressure, and becomes superconducting at 2.1 K at pressures above 16.3 kbar.11 Recently, LaMIn5 (M = Co, Rh, Ir) were reported.12 The structure of these layered HoCoGa5-type13 compounds is described in detail and consists of MIn2 rectangular prisms inserted between layers of face-sharing LaIn3 cuboctahedra.12 As part of our effort to examine the structure and determine the properties of other rare-earth-analogues, we have grown single crystals of an isostructural compound, ErCoIn5. Herein we report the synthesis, structural characterization, transport and magnetization properties of ErCoIn5 and compare to LaCoIn5.
FF3.7.2
Experimental Synthesis. The elements Er (99.9%, ingot), Co (99.998%, powder) and In (99.99%, shot) were purchased from Alfa Aesar. The ingot was cut into smaller pieces while the powder and shot were used as received and weighed. S
Data Loading...
