Lattice distortions in layered type arsenides LnTAs{sub 2} (Ln=La-Nd, Sm, Gd, Tb; T=Ag, Au): Crystal structures, electronic and magnetic properties

Journal Article · Mon Mar 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.12.021· OSTI ID:21372513

Rutzinger, D; Bartsch, C ^[1]; Doerr, M ^[2]; Rosner, H ^[3]; Neu, V ^[4]; Doert, Th ^[1]; Ruck, M ^[1]

---

1. Anorganische Chemie, Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, D-01062 Dresden (Germany)
2. Institut fuer Festkoerperphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany)
3. Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Str. 40, D-01187 Dresden (Germany)
4. IFW Dresden, Institut fuer metallische Werkstoffe, Helmholtzstr. 20, D-01069 Dresden (Germany)

The lanthanide coinage-metal diarsenides LnTAs{sub 2} (Ln=La, Ce-Nd, Sm; T=Ag, Au) have been reinvestigated and their structures have been refined from single crystal X-ray data. Two different distortion variants of the HfCuSi{sub 2} type are found: PrAgAs{sub 2}, NdAgAs{sub 2}, SmAgAs{sub 2}, GdAgAs{sub 2}, TbAgAs{sub 2}, NdAuAs{sub 2} and SmAuAs{sub 2} crystallize as twofold superstructures in space group Pmcn with the As atoms of their planar layers forming zigzag chains, whereas LaAgAs{sub 2}, CeAgAs{sub 2} and PrAuAs{sub 2} adopt a fourfold superstructure (space group Pmca) with cis-trans chains of As atoms. The respective atomic positions can be derived from the HfCuSi{sub 2} type by group-subgroup relations. The compounds with zigzag chains of As atoms exhibit metallic behaviour while those with cis-trans chains are semiconducting as measured on powder pellets. The majority of the compounds including 4f elements show antiferromagnetic ordering at T{sub N}<20 K. - Text3: Zigzig vs. cis-trans.

• OSTI ID: 21372513
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 3; Other Information: DOI: 10.1016/j.jssc.2009.12.021; PII: S0022-4596(09)00593-3; 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
ARSENIDES
CRYSTAL STRUCTURE
GOLD COMPOUNDS
LAYERS
MAGNETIC PROPERTIES
MONOCRYSTALS
RARE EARTH COMPOUNDS
SILVER COMPOUNDS
SPACE GROUPS
ARSENIC COMPOUNDS
CRYSTALS
MAGNETISM
PHYSICAL PROPERTIES
PNICTIDES
SYMMETRY GROUPS
TRANSITION ELEMENT COMPOUNDS