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Structure and superconductivity of LiFeAs
Michael J Pitcher1, Dinah R Parker, Paul Adamson
1Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, UK OX1 3QR.
Chemical Communications (Cambridge, England)
|November 26, 2008
Summary
Superconductivity was observed in lithium iron arsenide compounds up to 16 K. This indicates that superconducting anionic iron arsenide layers can form in various crystal structures.
Area of Science:
- Solid State Chemistry
- Materials Science
- Superconductivity
Background:
- Lithium iron arsenide (LiFeAs) is a well-known superconductor.
- Investigating related compounds can reveal new superconducting materials and mechanisms.
Purpose of the Study:
- To explore superconductivity in lithium iron arsenide phases near LiFeAs.
- To understand the structural diversity of superconducting anionic iron arsenide layers.
Main Methods:
- Synthesis and characterization of lithium iron arsenide phases.
- Superconductivity measurements (e.g., electrical resistivity, magnetic susceptibility).
Main Results:
- Superconductivity observed in phases near LiFeAs at temperatures up to 16 K.
- Superconducting [FeAs](-) anionic layers were found in at least three different structure types.
- A wide range of As-Fe-As bond angles was observed in these structures.
Conclusions:
- Superconducting anionic iron arsenide layers are structurally versatile.
- The anti-PbO structure type is not unique for these superconducting layers.
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