Seven-Coordinate Ruthenium Atoms Sequestered in Praseodymium Clusters in the Chloride {RuPr₃}Cl₃

The first example for an endohedral transition-metal atom (Ru) sequestered in a seven-coordinate surrounding of rare-earth metal atoms (Pr) has been found for {RuPr3}Cl3. The monocapped trigonal prisms of Pr atoms share two rectangular faces, forming a zigzag chain with Ru−Ru distances of 308 pm. Intracluster bonding is dominated by Ru−Pr bonding with very little Ru−Ru bonding.