title: Rational synthetic tuning between itinerant antiferromagnetism and ferromagnetism in the complex boride series Sc2FeRu(5-n)RhnB2 (0<or=n<or=5).
abstract: Single crystals of the complex boride series Sc(2)FeRu(5-n)Rh(n)B(2) (n=1, 3, 4) were synthesized by arc-melting the elements in water-cooled copper crucibles under argon atmospheres and were chemically characterized by single-crystal XRD and EDX analyses. The new compounds are isotypic and crystallize in the tetragonal space group P4/mbm with Z=2, adopting a substitutional variant of the Ti(3)Co(5)B(2)-type structure. The magnetically active iron atoms are arranged in chains with intra- and interchain distances of about 3.02 and 6.60 A, respectively. Strong ferromagnetic interactions are observed for both Sc(2)FeRuRh(4)B(2) (64 valence electrons (VE), TC approximately 350 K, mu(a)=3.1 mu(B)) and Sc(2)FeRu(2)Rh(3)B(2) (63 VE, T(C) approximately 300 K, mu(a)=3.0 mu(B)), whereas antiferromagnetic interactions are found in the case of Sc(2)FeRu(4)RhB(2) (61 VE, T(N) approximately 10 K, mu(eff)=3.2): The magnetism of the entire Sc(2)FeRu(5-n)Rh(n)B(2) (0<or=n<or=5) series is discussed based on the variable valence-electron count and the resulting Fe-Fe bonding character, and it is also compared with other isoelectronic systems.
authors.affiliation: Institute of Inorganic Chemistry, RWTH Aachen University, 52056 Aachen, Germany. boniface.fokwa@ac.rwth-aachen.de
authors.forename: Boniface P T
authors.initials: BP
authors.lastname: Fokwa
authors.forename: Heiko
authors.initials: H
authors.lastname: Lueken
authors.forename: Richard
authors.initials: R
authors.lastname: Dronskowski