Nitrides halides

The third aspect, the stability range of solid electrolytes, is of special concern for alkaline-ion conductors since only a few compounds show thermodynamic stability with, e.g., elemental lithium. Designing solid electrolytes by considering thermodynamic stability did lead to very interesting compounds and the discovery of promising new solid electrolytes such as the lithium nitride halides [27]. However, since solid-state reactions may proceed very slowly at low temperature, metasta-... 

This structure is commonly adopted by oxides, nitrides halides, and sulfides MX, including the nonstoichiometric 3d transition-metal oxides TiO, VO, MnO, FeO, CoO, and NiO. 

The obtention of nitrides by thermal decomposition of the azides was only successful for the synthesis of [MNBr4]2- from [MN3Br5] . Thermolysis of MX5 with ammonium salts afforded a more general access to nitride halides in oxidation state V, or IV if higher temperatures were used.316,317 Oxo nitrides were obtained if moisture was admitted during the process.318... 

There are selected examples of the use of additional nitrogen sources such as NSC1, N2, and NC13 (Eqs. (29,30)). The molybdenum nitride halide complexes were isolated from the reaction of a MoVI complex and NSC1 in the presence of Cl- or F [34]. Cummins reported the remarkable reaction of low-valent Mom triamide with N2 (1 atm) to afford the corresponding nitride 80 (Eq. (29)). The presence of bulky amide ligands is critical to the success of the reaction, for it prevents the formation of the stable dimer [(ArRN)3Mo]2. 

Superconductivity has been observed in the intercalated layered nitride halides of general composition MNX (M = Zr, Hf X = Cl, Br, I). On intercalation, jS-ZrNCl and /3-HfNCl, become superconductors with transition temperatures of 13 and 25.5 K, respectively. The transition temperature of the electron doped /3-HfNCl is higher than that observed in any intermetallic compound. 

Nitride halides have been prepared in various ways, for example, Mg2NCl (also F, Br, I) by direct combination of metal nitride and halide, Mg3NF3 by the action of nitrogen on a mbcture of metal and halide at 900°C, and ZrNI by heating... 

A new selenium nitride halide (115) with a Se chemical shift of 3= 1294... 

We have included not only pure nitride materials but also many amides, azides, oxynitrides (but not nitrates and nitrites), nitride chalcogenides, and nitride halides. Specifically excluded are polymeric compounds (e.g. SxNy), cluster compounds (e.g. Sc2C12N), coordination compounds (e.g. [Pd(NS3)2]), ternary azides and amides, as well as ternary interstitial transition-metal nitrides. We have attempted to include all important structures and all type compounds. This review is also unique in that we attempt to evaluate the... 

The black, stoichiometric nitride Ba,N, is prepared directly from the elements or decomposition of the azide. It is poorly crystalline [ 159, 160], We have been unable to successfully index a neutron diffraction pattern, since it exhibits broad diffraction peaks. Ba,N with the anti-CdCl2 structure is reported [161]. Since Ba2NF [121], Ba2NH [162], and BalNH) 125. 138, 163] are known to have the rocksalt structure, we again suggest that the other nitride halides Ba, N.Y i.Y = Cl. Br, I) are also based on a stuffed anti-CdCl, structure [122, 164,165],... 

Uranium and thorium nitride halides are related to the above. The series A/N.Y (M = U. Th A = Cl. Br, I) have the PbFCI structure (see Fig. 23) [246, 247. 248]. The corresponding fluorides have the LaOF structure [249, 250] which is an ordered superstructure of fluorite with a rhombohedral or tetragonal distortion [251, 252]. UNF and I hNF. therefore, crystallize with MN4F4 cubes while the anions center the tetrahedral sites (see Fig. 24). Yellow ThNH crystallizes on a face-centered cubic lattice [253]. 

The nitride halides of zirconium arc polymorphic. The low-temperature forms of ZrNCl and Z.rNBr. as well as ZrNl and ZrNlNlI >) have the FeOCl structure-type ( 285. 289. 290], Above a few hundred degrees, ZrNCl and Z.rNBr transform to an ordered CdCF-type structure [291. 292]. 

Trade names PIutoni um Oxi de Nitride Halide Oxa1ate comp ex Halide... 

Sulphur-Nitrogen-Phosphonis Compounds.—Thermolysis of compounds of the t3rpe RgPCl N—SOgX (R = Cl, Me, or Ph X = F or Cl) has been shown 2 to result in the formation of the compounds R2P(0)C1 and [NS(0)X] . Pyrolysis of phosphorus-sulphur-nitride halides with longer chains yields, amongst others, the cyclic compounds (37) and (38). The... 

The unusual electron count of 1.5 e per Gd atom raises the question whether intercalation reactions are possible. Between the cluster chains the packing of Cl atoms offers approximately octahedral voids (edge lengths 3.82, 3.86 and 4.19 A, respectively). All experiments aimed at an occupation of these voids by cations of suitable size, e.g. Li" or Mg " ", have to date been unsuccessful (Corbett and Simon 1979). Surprisingly, voids in the partial lattice of the metal atoms can be occupied by interstitial atoms, although not in a reversible topochemical reaction. In contrast to the preceding structures with interstitial atoms in octahedral voids, in the nitride halides tetrahedral voids play a dominant role. 

The distinction between conductors and insulators depends on the conductivity which can vary by more than ten orders of magnitude. The charge carriers can be either electrons (or holes) or ions (or vacancies). Ionic conductivity implies a diffusion of matter inside the solid (gel) and/or at its surface and thus most ionic conductors are also very good ion-exchangers. Materials (oxides, nitrides, halides or polymers) can be divided into four groups according to their electrical properties. 

The ternary metal nitride halides MNX (M=Ti, Zr, Hf X=C1, Br, I) contain two types of layer-structured polymorphs having different types of two-dimensional metal nitride networks [22]. Both are band insulators, and changed into superconductors with moderately high transition temperatures Ts up to 25.5 K upon electron-doping by means of intercalation through the interlayer space. There are two-layered polymorphs in MNX a-form with the FeOCl structure and p-form with the SmSI structure. p-ZrNCl has been synthesized by the reaction of Zr metal or ZrH powders were subjected to reaction with NH Cl at about 650 °C. 

Ternary and higher intermetallic 5. Nitride halides and nitride sulfides 88... 

Nitride halides and nitride sulfides constitute another family of rare-earth-containing compounds. The variety concerns the richness of the different formulations as well as the nature itself of the compounds. Except in the case of nitride fluorides which have a clear salt behavior, nitrogen atoms generally do not play the same role as Cl" or S anions in some cases it is even difficult to know whether the borderline between a valence compound and a cluster compound has not been crossed. 

Mattausch et al. (1996) have mentioned the preparation of other new ternary nitride halides containing cerium and/or bromine with the formula CeaCleN, CeaBr N, Ce2Br3N and Gd2Br3N. 

Perovskite, which is first used to describe the oxides CaTiOs, is now extensively referring to oxides with ABO3 structure, and sometimes also to the oxides with A2BO4 structure. In some eases, earbides, nitrides, halides, and hydrides also have the ABO3 structure,[l] but practically perovskite refers to the oxides compounds. In this context, if not specified, perovskite means an oxide compound having the ABO3 or A2BO4 structure. 

---