Chemical Modification of High-Temperature Superconducting Iron Pnictides: New Chemical Compounds and Characterization

• Applicant: Professor Dr. Rainer Niewa
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Theoretical Condensed Matter Physics
• Term: from 2010 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 168575949

Newly discovered iron pnictide superconductor materials will be prepared in pure form and subsequently modified by selected chemical reactions. Those reactions involve ion exchange of alkali and alkaline-earth metal ions by different versatile metal ions, chemical (de)intercalation of alkali and alkaline-earth metal ions and oxidation of the starting compound leading to hole doping of the iron pnictide layer, oxide ion extraction via reduction of the starting compound resulting in electron doping of the iron pnictide layer as well as solvatization. All reactions serve the aim not only to change the electronic situation within the iron pnictide layers but to vary distance and/or relative orientation of those layers and chemical bonding situation to the interconnecting species. For crystal growth in later stage of the project we aim to conduct the reactions in a topochemical fashion. From the study of the resulting properties of the new compounds we expect fundamental insights in interdependencies of structure and properties.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1458: High Temperature Superconductivity in Iron Pnictides