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The increasing interest in nanoscale materials goes hand in hand with the challenge to reliably characterize the chemical compositions and structural features of nanosized objects in order to relate those to their physical properties. Despite efforts, the analysis of the chemical composition of individual multi-element nanoparticles remains challenging-from the technical point of view as well as from the point of view of measurement statistics. Here, we demonstrate that zero-field solid-state nuclear magnetic resonance (NMR) complements local, single particle transmission electron microscopy (TEM) studies with information on a large assembly of chemically complex nanoparticles. The combination of both experimental techniques gives information on the local composition and structure and provides an excellent measurement statistic through the corresponding NMR ensemble measurement. This analytical approach is applicable to many kinds of magnetic materials and therefore may prove very versatile in the future research of particulate magnetic nanomaterials. [ABSTRACT FROM AUTHOR]

Layered metal chalcogenides such as MnBi 2 Se 4 are interesting candidates for a wide field of applications such as for thermo- and photoelectrics. High-quality single crystals are necessary in order to investigate their properties which can be prepared by chemical vapor transport (CVT). The CVT of MnBi 2 Se 4 has not been investigated until this point and is subject of the presented paper. We obtained needle-like MnBi 2 Se 4 single crystals with a length up to 15 mm. The magnetic characterization has shown an antiferromagnetic transition around 14 K. Additionally, electrical transport described MnBi 2 Se 4 as a narrow band-gap semiconductor ( E Gap =0.15 eV). Thermodynamic data for MnBi 2 Se 4 at room temperature were determined to H ° = − 305 KJ · mol − 1 , S =321 J K −1 ·mol −1 and C p = 167.568 + 25.979 · 10 − 3 · T J · K − 1 · mol − 1 , respectively. Our results on CVT-grown single crystals confirm reported data from literature and complete the data set for MnBi 2 Se 4 . [ABSTRACT FROM AUTHOR]