Single crystals halogens

For single crystals, the same method is applied, using an excess of metal and of halogen. After reaction, the mixture of the sulfide halide and the halide is heated to a temperature slightly above the melting point of the respective halide. Perfect, small crystals for X-ray determination are formed. The excess of the trihalide is removed by treatment with anhydrous alcohol 92, 93, 96). CeSI may also be prepared from the sulfides 68, 93) CeSCl is formed by reaction 4 92). 

Apart from characterization of the individual types of six-membered heterocycles by routine spectroscopic methods, several cationic cyclic diketiminato-phosphenium ions and 1,8-diamidonaphthalene-derived P-chlorophosphines and phosphenium ions, respectively, were characterized by single-crystal X-ray diffraction studies. The P-halogen- and P-hydroxy-substituted cyclic diketiminato-phosphenium ions 28... 

In general, in Part II we apply the same pattern of analysis to the numerous published vibrational spectra derived from the adsorption of alkynes, alkanes, and aromatic hydrocarbons. In addition, we summarize recently obtained spectroscopic results characterizing hydrocarbon species obtained by thermal, photochemical, or electron-bombardment dissociation of halogen- or nitrogen-substituted alkanes on single-crystal metal surfaces. The hydrocarbon surface species so obtained are normally as anticipated from the replacement of the heteroatoms by surface metal atoms. The... 

The fact that chloro and fluoro substitutions change the packing pattern dramatically in the presence of all the other interactions mentioned shows that the contributions to the stability of the crystal structures from the halogen atom interactions (X---C, X -O, and X---H) predominate. The results of the low-temperature single-crystal x-ray analysis of Cl and F are relevant here [42], In this crystal, no short F- -F contact was observed (2.92 A), whereas the interlayer intermolecular Cl- - Cl contact was shorter (3.07 A) than the sum of the van der Waals radii, showing that the F- -F interaction is not significant. 

Synthesis of single crystals of TBPDA (Cgo)2 was described elsewhere [4], Photoconductivity was excited by white light of a 150 W halogen tube. Photoconductivity was characterized by current T running through indium contacts attached to one of the faces of the samples with silver paste. The contacts were under direct voltage of 10-50 V. Current values were measured with a charge amplifier connected with PC. The cell filled with the sample was put in a resonator of a standard Radiopan SE/X 2547 spectrometer. 

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