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The title complex, (1,4,7,10,13,16-hexaoxacyclooctadecane-1κ⁶O)(μ-oxalato-1κ²O¹,O²:2κ²O^1′,O^2′)triphenyl-2κ³C-potassium(I)tin(IV), [KSn(C₆H₅)₃(C₂O₄)(C₁₂H₂₄O₆)] or K[18-Crown-6][(C₆H₅)₃SnO₄C₂], was synthesized. The complex consists of a potassium cation coordinated to the six oxygen atoms of a crown ether molecule and the two oxygen atoms of the oxalatotriphenylstannate anion. It crystallizes in the monoclinic crystal system within the space groupP2₁. The tin atom is coordinated by one chelating oxalate ligand and three phenyl groups, forming acis-trigonal–bipyramidal geometry around the tin atom. The cations and anions form ion pairs, linked through carbonyl coordination to the potassium atoms. The crystal structure features C—H...O hydrogen bonds between the oxygen atoms of the oxalate group and the hydrogen atoms of the phenyl groups, resulting in an infinite chain structure extending alonga-axis direction. The primary inter-chain interactions are van der Waals forces. 

Crystals of the title salt, (C₈H₂₀N)[Sn(C₆H₅)₃(C₂H₂O₂S)], comprise diisobutylammonium cations and mercaptoacetatotriphenylstannate(IV) anions. The bidentate binding mode of the mercaptoacetate ligand gives rise to a five-coordinated, ionic triphenyltin complex with a distortedcis-trigonal–bipyramidal geometry around the tin atom. In the crystal, charge-assisted ammonium-N—H...O(carboxylate) hydrogen-bonding connects two cations and two anions into a four-ion aggregate. Two positions were resolved for one of the phenyl rings with the major component having a site occupancy factor of 0.60 (3). 

The asymmetric unit in the title salt, (C₈H₂₀N)₂[SnCl₄(C₇H₄Cl₂F₃)₂], features a di-isobutylammonium cation in a general position and a diorganotin tetrachloride dianion,i.e. tetrachloridobis(3-trifuoromethylphenyl)stannate(IV), located on a centre of inversion; the Sn^IVatom is octahedrally coordinated. In the crystal, charge-assisted N⁺—H...Cl hydrogen bonds along with C—H...F contacts occur within supramolecular layers that interdigitate along thea-axis direction. 

N -(5-Cyanononan-5-yl)benzamide, C 17 H 24 N 2 O, synthesized from the reaction between benzoyl chloride and 2-amino-2-butylhexanenitrile, is an important intermediate in amino acid synthesis. Intermolecular N—H...O and C—H...O hydrogen bonds with N...O and C...O distances of 3.083 (2) and 3.304 (2) Å, respectively, link adjacent molecules into chains along the a axis. The dihedral angle between the mean plane of the phenyl group and the plane of the amide group is 19.504 (4)°. 

When a moderately intense, few-picosecond-long laser pulse ionizes gas to produce an underdense plasma column, a linear relativistic plasma wave or wake can be excited by the self-modulation instability that may prove useful for multi-bunch acceleration of externally injected electrons or positrons to high energies in a short distance. At the same time, due to the anisotropic temperature distributions of the ionized plasma electrons, the Weibel instability can self-generate magnetic fields throughout such a plasma on a few picoseconds timescale that can persist even longer than the lifetime of the wake. In the present paper, we first show using simulations that both these effects do indeed co-exist in space and time in the plasma. Using our simulations, we make preliminary estimates of the contribution to the transverse emittance growth of an externally injected beam due to the Weibel magnetic fields in a few-millimeter-long plasma. We then present the results of an experiment that has allowed us to measure the spatiotemporal evolution of the magnetic fields using an ultrashort relativistic electron probe beam. Both the topology and the lifetime of the Weibel instability induced magnetic fields in the experiment are in reasonable agreement with the fields induced by the Weibel instability in the simulations.