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Crystal orbital Hamilton population (COHP) bonding analysis has predicted that ScPd 3 B 0.5 is the least stable compound of the entire series Sc 2 Ir 6-x Pd x B. Here, we report a systematic study of Sc 2 Ir 6-x Pd x B (x=3, 5 and 6) by means of 11 B nuclear magnetic resonance (NMR), Knight shift (K) and nuclear spin-lattice relaxation rate (1/T 1 ). NMR results combined with theoretical band structure calculations provide a measure of s- and non-s-character Fermi-level density of states. We present direct evidence that the enhanced s-state character of the Fermi level density of states (DOS) in ScPd 3 B 0.5 reduces the strength of the B 2p and Pd 4d hybridized states across the entire Sc 2 Ir 6-x Pd x B series. This hybridization strength relates to the opening of a deep pseudogap in the density of states of Sc 2 IrPd 5 B and the chemical bonding instability of ScPd 3 B 0.5 . This study is an experimental realization of a chemical fine-tuning of the electronic properties in intermetallic perovskites., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synergistic combination of experiment and density functional theory has led to the discovery of the first ferromagnetic material, Nb6Fe(1-x)Ir(6+x)B8, containing in its crystal structure iron chains embedded in stacked B6 rings. The strong ferromagnetic Fe-Fe interactions found in the iron chains induce an unexpected strengthening of the B-B interactions in the B6 rings. Beside these strong B-B interactions, strong interlayer metal-boron bonds (Ir-B and Nb-B) ensure the overall structural stability of this phase, while the magnetic Fe-Fe interactions are mainly responsible for the observed ferromagnetic ordering below T(C)=350 K., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Members of the solid solution series of CeRu(1-x)Ni(x)Al can be obtained directly by arc melting of the elements. The presented compounds with 0.1 ≤ x ≤ 0.85 crystallize in the orthorhombic space group Pnma (No. 62) in the LaNiAl structure type, while for 0.9 ≤ x ≤ 1, the hexagonal ZrNiAl-type structure is found. The orthorhombic members exhibit an anomaly in the trend of the lattice parameters as well as an interesting behavior of the magnetic susceptibility, suggesting that the cerium cations exhibit no local moment. Besides the mixed-valent nature of the cerium cations, valence fluctuations along with a change in the cerium oxidation state depending on the nickel content have been found. The oxidation state has been determined from the magnetic data and additionally by XANES. Density functional theory calculations have identified the shortest Ce-Ru interaction as decisive for the stability of the orthorhombic solid solution.