Highlights at a glance

Unconventional Spin State in Pr₃Fe₃Sb₇

An unusual magnetic behavior was discovered in the rare earth iron antimonide Pr₃Fe₃Sb₇, which arises from a complex interplay of 3d and 4f magnetism. Crystal growth in a molten bismuth flux allowed the in-depth study of the bulk magnetic and electrical transport properties. A combined approach by extensive magnetization measurements, Mößbauer spectroscopy and neutron diffraction revealed the magnetic structure and the competing interactions of two different substructures.

A MINERAL PUMP FOR GOLD IN THE EARTH’S CRUST

To form an ore deposit, gold needs to be concentrated from a thousand up to a million times more than its average abundance in the Earth's crust (only about 1 mg per ton of rock). In nature, only very few minerals, namely arsenian pyrite and arsenopyrite, are known to present such enrichment factors for gold. However, despite the enormous implications, the state of this ‘invisible' gold and the cause of its entrapment in these sulfides remained one of the greatest mysteries in the history of the study of ore deposits.

Reaction mechanism of the polyol process in the intermetallic Bi-Ni system

By trapping intermediates using a synthesis microwave, the formation mechanism of BiNi particles in the polyol process was revealed. A successive reduction with a subsequent diffusion process was determined. The reaction is dependent on various parameters, which have been investigated as well.

Dissolution of metal oxides in ionic liquid

The ionic liquid [Hbet][NTf2] is suitable for the dissolution of numerous metal oxides at low temperature. Starting from a resulting complex compound, first steps towards downstream chemistry were made.

Hydroflux Synthesis of oxo hydroxoferrate K_2–xFe₄O_7–x(OH)_x

Reaction of iron(III) nitrate in a potassium hydroxide hydroflux leads to the oxo-hydroxoferrate(III) K_2−xFe₄O_7–x(OH)_x. This compound shows an unusual vacancy ordering of the potassium positions and decomposes topotactically into β’’ or β-aluminate-type K_1+x’Fe₁₁O₁₇.

Low-Temperature Ordering in the Cluster Compound (Bi8)Tl[AlCl4]3

Via reaction in the ionic liquid [BMIm]Cl·4AlCl₃ we recently succeeded to synthesize (Bi₈)Tl[AlCl₄]₃. In the cluster compound, that - at room temperature - may be regarded as a perovskite structure type with two complex ions, low temperature ordering of bismuth polycations could be observed.

Novel bonding situation between copper and bismuth

Copper and bismuth typically form binary compounds only under extreme conditions. However, we recently succeeded in synthesizing the intermetalloid cluster (CuBi8)3+ under mild reaction conditions. 

From graphite and nitrogen to CCN^3– in just one step

The elements carbon and nitrogen are generally unreactive. Reactive precursors like ammonia are thus employed for C–N bond-formation in organic synthesis. Surprisingly, the synthesis of CCN^3– suceeded from the elements – a quasi organic molecular anion postulated decades ago. The anion is stabilized in the bulk host framework of the nitridometalate Ba₅[TaN₄][C₂N].