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Low- and high-temperature (lt, ht) modifications of AlPS4 are prepared by solid state reaction of AlP and 10% excess S (evacuated silica tubes, 923 K, 30 d for the lt modification, 1023 K, 30 d, for the ht modification).

The first metastable iron-based superconductor of mean composition Na0.9Fe1.7As2 is prepared by topochemical deintercalation of Na+ ions from solid NaFeAs with iodine in THF at room temperature for 40 h.

The structures of Ce4I6CN and disordered Ce6I9C2N phases are determined by single crystal XRD, HRTEM, and SAED.

Thin films of GeSb2Te4 and Ge2Sb2Te4 are deposited on inert substrates by dc magnetron sputtering from stoichiometric compound targets and characterized by powder XRD and HRTEM.

The new delafossite type compounds AgLi1/3M2/3O2 (M: Rh, Ir) are synthesized by reaction of Li2RhO3 and Li2IrO3 in a AgNO3/KNO3 (2:1) melt (sealed glass tube, Ar, 623 K, 350 h).

[C13H28N2] 5Cu2.1In17.9S33 ·17H2O is synthesized from a mixture of CuS, In, S, 4,4′-trimethylenedipiperidine, H2O, and ethyleneglycol (autoclave, 190 °C, 5 d

The new title compounds are prepared by reactions of stoichiometric mixtures of the elements (1100 °C for 3 d) followed by annealing at 1300—1500 °C for 48—72 h.

Ag3Au1.1Te2 is synthesized from the elements in evacuated quartz ampules at 700 °C and characterized by HRTEM, SEM, and magnetoresistance measurements.

Two new subnitrides in the title system and three Li—In—Ba intermetallic phases are characterized by single crystal XRD and TEM.

In5S5Cl belongs to the group of mixed valence indium compounds with indium occurring simultaneously in three oxidation states (In5S5Cl = In+(In2)4+2In3+5S2–Cl–). It was shown in an earlier work that In5S5Cl obtained from InCl3, indium and sulfur at 550 °C, crystallises in a monoclinic structure type in contrast to the orthorhombic bromide, In5S5Br. The main difference of both structure types is an ordered mutual exchange of In+ and (In2)4+ in specific crystallographic positions. This exchange is possible due to the almost identical coordination pattern of both ions. A closer inspection of the real structure of monoclinic In5S5Cl by High Resolution Transmission Microscopy (HRTEM) already showed the presence of small orthorhombic domains in the real structure of this compound. Now we also obtained macroscopic quantities of orthorhombic In5S5Cl by the reaction of InCl3, indium and sulfur at reaction temperatures below 500 °C (Pmn21, a = 3.907(1) A, b = 9.021(2) A, c = 14.866(3) A, Z = 2). The new polymorph is analysed by X-ray single crystal and X-ray powder diffraction and HRTEM investigations.

A group of solids with the general composition A2In12Q19 (A = K, Tl, NH4; Q = Se, Te) is characterized by combined Xray single-crystal and high-resolution transmission-electron microscopy (HRTEM). Similar nanosize domains with variable sizes and complex internal structures are common to all three compounds. Although a partial ordering of domains for the bulk of K2In12Se19 is dominating, the observed ordering patterns in microdomains range from total random orientation to a pattern with a ninefold superstucture (rare precursor phase not stable under HRTEM conditions). In spite of testing various synthesis conditions it was not possible to avoid these unusual structural features for K2In12Se19, which are apparently intrinsic. The formation of significantly larger domains is observed for K2In12Se19–xTex and K2–yTlyIn12Se19 and results in a twofold superstructure that can be observed with X-ray diffraction also on a macroscopic scale. (NH4)- In12Se19 is a special case where an initial weak ordering is observed that is characterized by ring X-ray reflections forming hexagons around certain reciprocal lattice positions. This pattern has apparent similarities to K2In12Se19 but is not stable in the HRTEM. Instead, it disappears rapidly and is finally replaced by a twofold superstructure similar to K2In12Se19–xTex and K2–yTlyIn12Se19. The reason was identified as a combined process of domain broadening and NH3 evaporation. As observed for K2In12Se19 at T 473 K, the superstructure reflections disappear. Surprisingly, the pseudobinary phase In2Q3 (Q: chalcogen) shows strong structural similarities to K2In12Se19 with respect to the internal structure of the nanodomains. Their three-dimensional arrangement, however, and the resulting superstructure are closer related to K2In12Se19–xTex and K2–yTlyIn12Se19.

A new Ti 5 Te 4 -type compound, Zr stabilized hafnium telluride was discovered and characterized with electron crystallography. Microanalyses and preparative work show that Zr stabilizes Ti 5 Te 4 -type hafnium telluride and destabilizes the competing phase, Hf 3 Te 2 .