Oxyhalides and Related Compounds

Oxyhalides and Related Compounds. Heat capacities, free energies, enthalpies, and entropies have been calculated for CrOF and CrOCl in the temperature range 100—6000 K.  

Raman spectral studies suggest that liquid Cr02F2 exists primarily as a monomer with C2 symmetry, whereas solid Cr02F2 has a fluorine-bridged polymeric structure retaining terminal Cr—O bonds. 

Ph M (M = As or P) salts of the CrOCl anion have been isolated by reduction of CrOjClj with HCl in acetic acid and precipitation with Ph MCl. Magnetic moments measured were 1.76 and 1.72 BM for M = As and P respectively. The single crystal electronic spectrum of (Ph As)CrOCl4 has been recorded and the bands assigned with the aid of ab initio MO calculations.  

The complex ion CrOBrj has been isolated as the relatively stable bipy salt. The value of //, 1.75 BM, and the g value, 1.999, show, as expected, that the orbital moment is quenched in a low-symmetry ligand field, the distortion being caused by the strong metal-oxygen bond. 

The system CrF3-Nb20j gives rise to the solid solution phase Cr Nb, 6—- 2x Monoclinic (high temperature) and orthorhombic (low temperature) phases have been observed for Na2Cr Ti Oi4F2, the two phases are isotypic with Na2Cr2 Ti,0,F2.  

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Niobium(v) and Tantalum(v).—Halides, Oxyhalides and Related Compounds. The ability of TaFj to act as a fluoride ion acceptor in anhydrous HF has been exploited in the preparation of salts of the AsH, HjS, and PH ions... 

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