@misc{GrohBreternitzAhmedetal., author = {Groh, Matthias F. and Breternitz, Joachim and Ahmed, Ejaz and Isaeva, Anna and Efimova, Anastasia and Schmidt, Peer and Ruck, Michael}, title = {Ionothermal Synthesis, Structure, and Bonding of the Catena-Heteropolycation 1∞[Sb2Se2]+}, series = {Zeitschrift f{\"u}r anorganische und allgemeine Chemie}, volume = {641}, journal = {Zeitschrift f{\"u}r anorganische und allgemeine Chemie}, number = {2}, issn = {1521-3749}, doi = {10.1002/zaac.201400543}, pages = {388 -- 393}, abstract = {The reaction of antimony and selenium in the Lewis-acidic ionic liquid 1-butyl-3-methyl-imidazolium tetrachloridoaluminate, [BMIm]Cl·4.7AlCl3, yielded dark-red crystals of [Sb2Se2]AlCl4. The formation starts above 160 °C; at about 190 °C, irreversible decomposition takes place. The compound crystallizes in the triclinic space group Pequation image with a = 919.39(2) pm, b = 1137.92(3) pm, c = 1152.30(3) pm, α = 68.047(1)°, β = 78.115(1)°, γ = 72.530(1)°, and Z = 4. The structure is similar to that of [Sb2Te2]AlCl4 but has only half the number of crystallographically independent atoms. Polycationic chains 1∞[Sb2Se2]+ form a pseudo-hexagonal arrangement along [01-1], which is interlaced by tetrahedral AlCl4- groups. The catena-heteropolycation 1∞[Sb2Se2]+ is a sequence of three different four-membered [Sb2Se2] rings. The chemical bonding scheme, established from the topological analysis of the real-space bonding indicator ELI-D, includes significantly polar covalent bonding in four-member rings within the polycation. The rings are connected into an infinite chain by homonuclear non-polar Sb-Sb bonds and highly polar Sb-Se bonds. Half of the selenium atoms are three-bonded.}, language = {en} } @misc{ZeugnerKaiserSchmidtetal., author = {Zeugner, Alexander and Kaiser, Martin and Schmidt, Peer and Menshchikova, Tatiana V. and Rusinov, Igor P. and Markelov, Anton V. and Van den Broek, Wouter and Chulkov, Evgueni V. and Doert, Thomas and Ruck, Michael and Isaeva, Anna}, title = {Modular Design with 2D Topological-Insulator Building Blocks: Optimized Synthesis and Crystal Growth and Crystal and Electronic Structures of BiₓTeI (x = 2, 3)}, series = {Chemistry of Materials}, volume = {29}, journal = {Chemistry of Materials}, number = {3}, issn = {0897-4756}, doi = {10.1021/acs.chemmater.6b05038}, pages = {1321 -- 1337}, abstract = {Structural engineering of topological bulk materials is systematically explored with regard to the incorporation of the buckled bismuth layer [Bi₂], which is a 2D topological insulator per se, into the layered BiTeI host structure. The previously known bismuth telluride iodides, BiTeI and Bi₂TeI, offer physical properties relevant for spintronics. Herewith a new cousin, Bi₃TeI (sp.gr. R3m, a = 440.12(2) pm, c = 3223.1(2) pm), joins the ranks and expands this structural family. Bi₃TeI = [Bi₂][BiTeI] represents a stack with strictly alternating building blocks. Conditions for reproducible synthesis and crystal-growth of Bi₂TeI and Bi₃TeI are ascertained, thus yielding platelet-like crystals on the millimeter size scale and enabling direct measurements. The crystal structures of Bi₂TeI and Bi₃TeI are examined by X-ray diffraction and electron microscopy. DFT calculations predict metallic properties of Bi₃TeI and an unconventional surface state residing on various surface terminations. This state emerges as a result of complex hybridization of atomic states due to their strong intermixing. Our study does not support the existence of new stacking variants BiₓTeI with x > 3; instead, it indicates a possible homogeneity range of Bi₃TeI. The series BiTeI-Bi₂TeI-Bi₃TeI illustrates the influence of structural modifications on topological properties.}, language = {en} } @misc{VinokurovaKnorrEfimovaetal., author = {Vinokurova, Ekaterina and Knorr, Monika and Efimova, Anastasia and Ovchinnikov, Alexander and Schmidt, Peer and B{\"u}chner, Bernd and Isaeva, Anna and Roslova, Maria}, title = {Microstructural evolution of layered K-doped RuCl3 during annealing traced by thermogravimetric analysis and 3D electron diffraction}, series = {Zeitschrift f{\"u}r Anorgische und Allgemeine Chemie}, volume = {649}, journal = {Zeitschrift f{\"u}r Anorgische und Allgemeine Chemie}, number = {19}, issn = {0044-2313}, doi = {10.1002/zaac.202300141}, pages = {1 -- 8}, abstract = {Nanoscale phase separation was induced in the K-doped RuCl3 van der Waals material by annealing, and studied with the goal to find a natural design strategy for the formation of two-dimensional architectures as an alternative to the costly and time-consuming experimental artificial growth methods. Phase conversion was traced by means of thermogravimetric analysis combined with mass spectrometry. The local crystal structure of co-existing K3Ru2Cl9 domains with the sizes of about 100 nm was solved by 3D electron diffraction.}, language = {en} }