Bromido(2,4,6-trimethyl­phen­yl)mercury(II)

Mol­ecules of the title compound, [HgBr(C₉H₁₁)], are located on a crystallographic twofold rotation axis. Due to the mol­ecular symmetry, the Hg^II atom is linearly coordinated by the ipso-C of the mesityl group and the Br atom. In the crystal, mol­ecules lie in planes parallel to (001).

trans-Dichloridobis(triphenyl­phosphane-κP)palladium(II) benzene hemisolvate

The title complex, [PdCl₂(C₁₈H₁₅P)₂]·0.5C₆H₆, has the Pd^II ion in a square-planar coordination mode (r.m.s. deviation for Pd, P and Cl atoms = 0.024 Å) with the PPh₃ and Cl ligands mutually trans. The benzene solvent mol­ecule is located about a crystallographic inversion centre. The title complex is isostructural with trans-dichloridobis(triphenyl­phosphane)­palladium(II) 1,4-dichloro­benzene sesquisolvate [Kitano et al. (1983). Acta Cryst. C39, 1015–1017].

Iodido(tri-tert-butyl­phosphane-κP)gold(I)

The Au^I atom of the title compound, [AuI(C₁₂H₂₇P)], shows an almost linear coordination, with a P—Au—I angle of 178.52 (3)° [Au—P = 2.2723 (14) Å and Au—I = 2.5626 (6) Å].

A triclinic polymorph of bis­(μ-di-tert-butyl­phosphanido)bis­[(di-tert-butyl­phosphane)palladium(I)]

A new polymorph of the title compound, [Pd₂(C₈H₁₈P)₂(C₈H₁₉P)₂], has been found. It belongs to the triclinic P-1 space group, whereas the known form [Leoni, Sommovigo, Pasquali, Sabatino & Braga (1992), J. Organo­met. Chem. 423, 263–270] crystallizes in the monoclinic C2/c space group. The title compound features a dinuclear palladium complex with a planar central Pd₂(μ-P)₂ core (r.m.s. deviation = 0.003 Å). The Pd—Pd distance of 2.5988 (5) Å is within the range of a Pd^I—Pd^I bond. The mol­ecules of both polymorphs are located on a crystallographic centre of inversion. The mol­ecular conformations of the two polymorphs are essentially identical. The crystal packing patterns, on the other hand, are slightly different.

Redetermination of (acetonitrile-κN)dicarbon­yl(η⁵-cyclo­penta­dien­yl)iron(II) tetra­fluoridoborate

The crystal structure of the title compound, [Fe(C₅H₅)(CH₃CN)(CO)₂]BF₄, of which only the coordinates of the non-H atoms of the cation have previously been reported [Fadel et al. (1979). Z. Anorg. Allg. Chem. 453, 98–106] has been redetermined. The Fe^II atom in the complex cation is coordinated by a cyclo­penta­dienyl ring, two carbonyl ligands and an acetonitrile mol­ecule displaying a three-legged piano stool structure. Three of the four F atoms of the BF₄⁻ anion are disordered over two sets of sites, with a site-occupancy factor of 0.709 (10) for the major occupied site.

Sodium penta­fluoro­phenyl­borate

The crystal structure of the title compound, Na[(C₆F₅)BH₃], is composed of discrete anions and cations. The sodium cations are surrounded by four anions with three short Na...B [2.848 (8), 2.842 (7) and 2.868 (8) Å] and two short Na...F contacts [2.348 (5) and 2.392 (5) Å], forming a three-dimensional network. The anion is the first structural example of a pentafluorophenyl ring carrying a BH₃ group.