Magnetic and thermodynamic properties of NdT{sub 2}Ge{sub 2} (T=Pd, Ag) compounds

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2010.01.031· OSTI ID:21372554

Gondek, L ^[1]; Penc, B ^[2]; Kaczorowski, D ^[3]; Baran, S ^[2]; Hoser, A; Gerischer, S ^[4]; SzytuLa, A ^[2]

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1. Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow (Poland)
2. M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland)
3. W. Trzebiatowski Institute of Low Temperature and Structural Research, Polish Academy of Sciences, PO Box 1410, 50-950 WrocLaw (Poland)
4. BENSC, Helmholtz-Zentrum Berlin, Glienicker Str. 100, D-14 109 Berlin (Germany)

Physical properties of NdPd{sub 2}Ge{sub 2} and NdAg{sub 2}Ge{sub 2}, crystallizing with the tetragonal ThCr{sub 2}Si{sub 2}-type crystal structure, were investigated by means of magnetic, calorimetric, electrical transport as well as by neutron diffraction measurements. The specific heat studies and neutron diffraction measurements were performed down to 0.30 K and 0.47 K, respectively. Both compounds exhibit antiferromagnetic ordering below T{sub N} equal to 1.5 K for NdPd{sub 2}Ge{sub 2} and 1.8 K for NdAg{sub 2}Ge{sub 2}. Neutron diffraction data for the latter germanide indicate antiferromagnetic collinear structure described by the propagation vector k=(0.5, 0, 0.5). The Nd magnetic moments equal to 2.24(5) mu{sub B} at 0.47 K are aligned along the a-axis and have the +- sequence within the crystal unit cell. For NdPd{sub 2}Ge{sub 2} only very small Bragg peaks of magnetic origin were observed in the neutron diffraction patterns measured below T{sub N}, thus hampering determination of the magnetic structure. Both compounds exhibit metallic-like electrical conduction. From the specific heat data the crystal electric field (CEF) levels schemes were determined. Difference between the overall CEF splitting in the two compounds is correlated with their structural parameters. - Graphical abstract: Low-temperature specific heat of NdAg{sub 2}Ge{sub 2} under external magnetic fields. The lambda-like anomaly originates from onset of magnetic ordering below 1.80 K. Shifting the anomaly position towards the lower temperatures, when raising the magnetic field, hints at antiferromagnetic behaviors.

• OSTI ID: 21372554
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 4; Other Information: DOI: 10.1016/j.jssc.2010.01.031; PII: S0022-4596(10)00046-0; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIFERROMAGNETISM
BRAGG CURVE
CALORIMETRY
CRYSTALS
ELECTRIC CONDUCTIVITY
GERMANIDES
MAGNETIC FIELDS
MAGNETIC MOMENTS
MAGNETIC SUSCEPTIBILITY
NEODYMIUM COMPOUNDS
NEUTRON DIFFRACTION
PALLADIUM COMPOUNDS
SILVER COMPOUNDS
SPECIFIC HEAT
TEMPERATURE RANGE 0000-0013 K
COHERENT SCATTERING
DIAGRAMS
DIFFRACTION
ELECTRICAL PROPERTIES
GERMANIUM COMPOUNDS
INFORMATION
MAGNETIC PROPERTIES
MAGNETISM
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SCATTERING
TEMPERATURE RANGE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS