A discharge flow-photoionization mass spectrometric system coupled to a synchrotron is employed to study intermediates and products of sulfur radical reactions related to atmospheric chemistry. Sulfur radicals are generated from reactions of oxygen or chlorine atoms with sulfur compounds in a flow tube. The gaseous reaction products are sampled into the ionization region via a three-stage differential pumping scheme. Photoionization spectra and ionization energies are measured by dispersing synchrotron radiation to ionize the samples. Using this technique, photoionization spectra and ionization energies of HSO, CH₃SO, C₂H₅SO, HSCl, and some secondary reaction products, SSCl, HSSCl, HSSSH, CH₃SOH and CH₃SS(O)CH₃, were measured for the first time.

In the title compound, [HgCl₂(C₁₅H₂₆N₂)], the chiral alkaloid (6R,7S,8S,14S)-(−)-L-sparteine acts as a bident­ate ligand, with two Cl⁻ ligands occupying the remaining coordination sites, producing a distorted tetra­hedron. The N—Hg—N plane is twisted by 81.1 (2)° from the Cl—Hg—Cl plane. The mid-point of the NN line does not lie exactly on the Cl—Hg—Cl plane but is tilted towards one of the N atoms by 0.346 Å. Similarly, the mid-point of the ClCl line is tilted toward one of the Cl atoms by 0.163 Å. The packing structure shows that the complex is stabilized by two inter­atomic ClH contacts involving both Cl atoms and the methyl­ene or methine H atoms of the (−)-sparteine ligand.

The structure of the title compound, (C₁₀H₁₆N₂)[CuCl₄], comprises two crystallographically non-equivalent tetrahedral [CuCl₄]^2- anions, each of which is linked to two doubly protonated nicotinium cations via hydrogen bonds. There are two different types of hydrogen-bonding interactions present, namely (i) the protonated pyridinium groups exclusively form bifurcated hydrogen bonds to two cis-Cl atoms of both [CuCl₄]^2- units and (ii) the protonated pyrrolidinium groups exclusively form a two-center hydrogen bond with a chloride of both [CuCl₄]^2- units.

The title compound, C₂₄H₂₀Br₂N₂O₄, is an 18-membered tricycle including two isoxazole rings. The asymmetric unit contains one half of the formula unit; a centre of inversion is located at the centroid of the compound. The dihedral angle between adjacent isoxazole and benzene rings is 84.0 (2)°. The compound displays intra- and inter­molecular π–π stacking inter­actions between the isoxazole rings, the shortest centroid–centroid distances being 3.837 (3) and 3.634 (3) Å, respectively. The mol­ecules are stacked in columns along the a axis with short BrBr contacts [3.508 (1) Å].

In the title amide, C₁₆H₁₅F₂NO₃, the dihedral angle between the benzene rings is 53.7 (1)°. Mol­ecules are linked in the crystal structure by an inter­molecular N—HO hydrogen bond involving N—H and C=O functionalities of the amide group. A one-dimensional network is thus formed along the [001] direction. No significant inter­chain contacts are observed.