Nitride ions chemically behave different from oxide ions due to their greater charge and polarizability. For instance they are able to stabilize transition metals in especially low, positive oxidation states.
Our focus lies on the structural family of inverse perovskites. Their structure resembles regular perovskites, however, cations are exchanged for anions and vice versa. Like their regular relatives, many inverse perovskites exhibit attractive electric, magnetic and thermic properties.
It is not rare to encounter unexpected products, often with an interesting crystal structure and chemistry. Therefore, an important part of working on this subject is the structural elucidation and characterization of hitherto unknown compounds.
Syntheses are carried out under argon in metal ampoules sealed by arc welding. Alkali metals are used as flux to improve crystal growth. These are removed after the synthesis by dissolution in liquid ammonia at low temperatures.
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