Metal borides1 are inorganic solids that often show refractory properties, like super-hardness2 and very high-melting points. They may also prove to be exciting concerning their electronic structure, as shown for super-‐conducting magnesium diboride, MgB2,3 or samarium hexaboride, SmB6,4 which was recently described to be a topological insulator.
New investigations on nanoscale and bulk mono‐, di-tetra-, and hexaborides will be presented. Examples are MnB4, crystallizing similar to hypothetical tetragonal diamond but exhibiting an unexpected Peierls distortion,5,6 solid solutions of (M,M')B6 with good thermoelectric properties,7 and nanoscale metal borides that can be (ferro)magnetic.8 Synthesis, characterization, structures, and properties will be discussed.
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5 A. Knappschneider, C. Litterscheid, N.C. George, J. Brgoch, N. Wagner, J. Beck. J.A. Kurzman, R.
Seshadri, B. Albert, Angew. Chem. 126 (2014) 1710-1714, Int. Ed. Engl. 53 (2014) 1684-1688
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7 M. Gürsoy, M. Takeda, and B. Albert, J. Solid State Chem. 221 (2015) 191-195
8 S. Rades, S. Kraemer, R. Seshadri, B. Albert, Chem. Mater. (2014) 1549-1552