Cationic, neutral, and anionic arsenic and antimony halides formed binary arsenic and antimony azide species M(N(3))(4)(+), M(N(3))(4)(-), and M(N(3))(6)(-) (M = As, Sb) upon reaction with trimethylsilyl azide or sodium azide. The compounds were obtained as pure substances or salts, and their identity was established by vibrational spectroscopy and multinuclear NMR spectroscopy and partially by elemental analysis. Attempts to synthesize pentaazides, M(N(3))(5) (M = As, Sb), failed due to spontaneous decomposition of the compounds. Density functional theory (B3LYP) was applied to calculate structural and vibrational data. Vibrational assignments of the normal modes for the isolated azide compounds were made on the basis of their vibrational spectra in comparison with computational results. The molecular structures and vibrational spectra of the arsenic and antimony pentaazides have been investigated theoretically. These calculations (B3LYP) show minima structures (NIMAG = 0) for all reported compounds. It is shown that the M(N(3))(4)(+) (M = As, Sb) cations exhibit ideal S(4) symmetry and the M(N(3))(6)(-) anions (M = As, Sb) ideal S(6) symmetry. The structure of the hexaazidoarsenate(V) has been determined by X-ray diffraction as its pyridinium salt. [py-H][As(N(3))(6)] crystallizes in the triclinic space group P with a = 6.8484(7), b = 7.3957(8), and c = 8.0903(8) A, alpha = 91.017(2), beta = 113.235(2), and gamma = 91.732(2) degrees, V = 376.29(7) A(3), and Z = 1. The structure of the As(N(3))(6)(-) anion exhibits only S(2) symmetry but shows approximately S(6) symmetry. The calculated and experimentally observed structure as well as the calculated and observed IR and Raman frequencies for all azide species (except M(N(3))(5)) are in reasonable agreement.

The cover picture shows the X‐ray crystallographically determined structure of the hexaazidoarsenate(v) anion, which was produced by the simple reaction of trimethylsilylazide and [PPh4]+[AsCl6]− and can be isolated in the form of the [PPh4]+ salt. This is the first X‐ray structural analysis of an arsenic azide. The extremely nitrogen‐rich anion is almost S2 symmetric in the crystal. Unexpectedly, the compound obtained shows little inclination to explode. More information about these interesting compounds is reported by T. M. Klapötke et al. on page 2108 ff.

A catalyst preparative procedure is described that produces a high surface area alumina-supported palladium catalyst that yields an atypical chemisorbed carbon monoxide infrared spectrum. This inherently residue-free substrate provides a useful reference for evaluation of catalyst crystallite morphology and its effect on reactivity profiles.

Palladium(II) azide (1) was synthesized by reaction of palladium nitrate and sodium azide. 1 was characterized by AAS, IR, and 14N‐NMR spectroscopy. Bis(azido)bis(pyridine)palladium(II) (2) and tetramminepalladium tetraazidopalladate(II) (3) were synthesized by a high‐yield reaction. Both were characterized by X‐ray structural analysis, IR, Raman, and NMR spectroscopy.

-011Crystal Structures of (PPh 3 ) 2 Pd(N 3 ) 2 (I), (-As revealed by single crystal XRD, compounds (PPh