Structural Complexity From Powder X‐Ray Diffraction Data: Sr ₂₅ [Mn ₄₂ N ₅₀ ]: A New Member in the Family of Two‐Dimensional Intergrowth Nitridometalates

The new compound Sr 25 [Mn 42 N 50 ] (space group P , Pearson code hP 117, a = 17.9756(7) Å, c = 5.7935(2) Å) represents a new member in the family of layered nitridomanganates with complex crystal structures built up by two‐dimenisonal intergrowth. The crystal structure was solved and refined from synchrotron powder diffraction data. Mn shows an average oxidation state between +2 and +3 with no signs of charge ordering, consistent with the very narrow bandgap determined from the resistivity measurements. An extended network of MnMn bonding interactions in Sr 25 [Mn 42 N 50 ] results in quenching of paramagnetism. The atomic arrangement in Sr 25 [Mn 42 N 50 ] represents one type of building blocks found in another nitridomanganate, Ca 133 [Mn 216 N 260 ], whose crystal structure can be described as a two‐dimensional intergrowth of nanometer‐sized Ca 12 [Mn 19 N 23 ]‐ and Sr 25 [Mn 42 N 50 ]‐type “tiles”. With this approach, some magnetic properties of these materials can be predicted and possibly adjusted by crystal structure design.