Single phase powders of (Sr3N)Sb, (Sr3N)Bi ($Pm{\bar 3}m$, No. 221, Z = 1, Sb: a = 517.25(2) pm, V = 138.390(8) · 106 pm3, Bi: a = 520.691(8) pm, V = 141.170(4) · 106 pm3), (Ba3N)Sb, and (Ba3N)Bi (P63/mmc, No. 194, Z = 2, Sb: a = 753.33(3) pm, c = 664.45(3) pm, V = 326.56(2) · 106 pm3, Bi: a = 761.28(4) pm, c = 668.05(3) pm, V = 335.30(2) · 106 pm3) were obtained from reactions of melt beads of the respective elements with bulk compositions of A3E (A = Sr, Ba; E = Sb, Bi) in nitrogen atmosphere of ambient pressure at T = 1070 K (Sr) and T = 1120 K (Ba). The compositions were derived from chemical analyses and supported by Rietveld refinements based on powder X‐ray diffraction patterns. The Sr containing compounds crystallize in the cubic anti‐perovskite type arrangement, the Ba containing compounds in the hexagonal anti‐BaNiO3 structure type. Magnetic susceptibility and electrical resistivity data indicate that the compounds are diamagnetic semiconductors. The optical band gaps of (Sr3N)Sb and (Sr3N)Bi were determined by diffuse reflectivity to 1.15 eV and 0.89 eV, respectively. The experimental results are in agreement with electronic structure calculations. Chemical bonding is characterized in a simplified picture as ionic with significant orbital mixing.

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A high-power continuous-wave coherent light source at 253.7 nm is described. It is based on a solid-state Yb:YAG disk laser with two successive frequency doubling stages and is capable of generating stable output powers of up to 750 mW. Spectroscopy of the 6 (1)S(0)-6 (3)P(1) transition of mercury has been demonstrated.

Black powders of (Sr3Nx)Sn (x = 0.74(2), a = 523.51(5) pm), (Ba3Nx)Sn (x = 0.62(2), a = 552.93(1) pm), (Sr3Nx)Pb (x = 0.81(3), a = 524.22(1) pm) and (Ba3Nx)Pb (x = 0.826(4), a = 554.40(3) pm, Pm3¯m, No. 221, Z = 1) were obtained from reactions of melt beads of the respective metals with bulk compositions of A3E (A = Sr, Ba; E = Sn, Pb) in nitrogen atmosphere at temperatures in the range of 970 K ‐ 1220 K. The compositions were derived from chemical analyses, supported by Rietveld refinements based on powder X‐ray and neutron diffraction patterns taken on (Ba3Nx)Sn (x = 0.64(1); neutron diffraction: RBragg = 8.70 %, RF = 6.10 %; X‐ray diffraction: RBragg = 11.60 %, RF = 12.00 %). The phases crystallize in cubic anti‐perovskite type arrangements. Measurements of the magnetic susceptibility indicate a nearly temperature independent paramagnetism. The electrical resistivities are weakly temperature dependent with resistivities at 300 K in the order of 1 mΩ·cm. Electronic structure calculations on ordered superstructures of the composition (A3N2/3)E reveal the phases as intrinsic metals and suggest the tendency towards higher nitrogen site occupation (x > ⅔).

ScN was prepared in three different ways leading to single phase samples with low oxygen content in a broad range of particle sizes. Synthesis from the elements provides, in an exothermic reaction, brownish transparent single crystals (rock-salt structure type, space group Fm3 hm, a ) 451.2(1) pm, Z ) 4, R int ) 0.034, R1 ) 0.013, wR2 ) 0.018). From a decomposition reaction of Li 3 [ScN 2 ] fine brown powders (particle size ≈ 1 µm) were obtained. Via nitridation of intermetallic Sc-In phases even nanoscaled (<200 nm) ScN can be produced. The emerging In was converted to InI 3 and removed at comparable low temperatures (T max ) 453 K) by sublimation or extraction. Thermodynamic considerations enlighten the process. Crystal structure refinements, density measurements, and chemical analyses show an atomic ratio close to the ideal composition ScN with only a small vacancy concentration in the N-sublattice for all samples. Still, metal-like behavior in the electrical resistivity was observed ((F(300 K) -F 0 ) 1.1 × 10 -4 Ωcm, temperature coefficient 2.7 × 10 -3 K -1 ). This interpretation is in accordance with the magnetic susceptibility (temperatureindependent paramagnetism χ 0 ≈ 4 × 10 -6 emu/mol) and the observed band gap of ∆E ) 2.10(2) eV. The oxidation behavior dependence on the particle size is analyzed.

The cubic inverse Perovskites (Eu 3 O)In and (Eu 3 O)Sn were prepared from the metals and Eu 2 O 3 or SnO 2 , respectively. For (Eu 3 O)In the crystal structure analysis was performed on single crystal X-ray diffraction data (space group Pm3m, a ϭ 512.79(3) pm, Z ϭ 1, R gt (F) ϭ 0.022, wR(F 2 ) ϭ 0.044). The data indicated full occupancy on all sites and a fully ordered structure. According to magnetic susceptibility measurements and X-ray absorption spectroscopic data at the Eu L III edge both compounds contain europium in the 4f 7 (Eu 2ϩ ) electronic state. 559 ders ferromagnetically at 185(5) K, (Eu 3 O)Sn shows antiferromagnetic order at 31.4(2) K. Both compounds behave as metallic conductors in electrical resistivity measurements. However, (Eu 3 O)In may be classified a metal, while (Eu 3 O)Sn is more likely a heavily doped degenerated semiconductor or semimetal according to the absolute values of the resistivity.