Mixed-valent tetranuclear manganese complexes with an {MnII3MnIV} core

► Mixed-valent phenyl 2-pyridyl ketoxime complexes with an {MnII3MnIV-μ4-O} core. ► Different magnetisms as a function of differing structural details. ► First {MnII3MnIV-μ4-O}-core cationic complex with dominating antiferromagnetic interactions.