NaCl-type related phase

These non-existent allotropes, which are impurity-stabilized phases, are fee Sc, fee Y-Ce, the bcc Ho, Er, Tm and Lu and fee phases of Nd, Sm, Gd and Dy, some of which have been described as formed at room temperature during mechanical milling. A number of fee high-pressure polymorphs, for instance, are actually compounds, with a structure related to the NaCl-type, formed by reaction with O, N and/or H during mechanical milling (see also Alonso et al. 1992). 

The monophosphides REP (RE = La, Ce, Pr, Nd, Sm, Gd, Tb, Tm, Yb) crystallize in the NaCl-type structure at ambient pressure. All of them undergo phase transitions, some into a tetragonally distorted CsCl related structure (Ea, Pr, Nd) and the others into a more complicated unknown high-pressure phase (Sm, Gd, Tb, Tm, Yb) at pressures from 35 to 51 GPa, respectively. It might be that a disproportionation occurs, similar to that in Eu2As2. ... 

In order to clarify the relation between Ny and r fr, the structural type are plotted as functions of these two parameters for the present systems together with the other related compounds of A/(C, N) in Fig. 3. In this figure the data for the present systems obtained after the annealing under NH3 at 1173K was used. It is seen that there are two regions of structural type according to sample s Ny and r. r, one is the NaCl-type and another is the WC-type phase. In the case of Ny less than 10, only the NaCl-type phase with stoichiometric composition is formed independently of At A ve=10, the... 

The preparation and characterization of the two phases Caio- Si,2-2 As,(, and Caio, Si]2- Pi6 (0.66 X 2.50) have been described.Their structures are isotypic and crystallize with monoclinic symmetry, of space group they may be related to a slightly distorted NaCl-type. Their unit-cell parameters are included in Table 27. A comparison of the different methods of crystal growth of ZnSiP2, ZnSiAs2, and CdGeAs2 (chalcopyrite structures) has also been undertaken. " ... 

In and T1 monohalides are isoelectronic with the Sn and Pb monochalcogenides. The character of their structures, however, is different, although geometrically, the two structures are closely related. Common to both groups is, furthermore, the occurrence of NaCl-type phases and NaCl-type derivatives (see Table 51). CsCl-type modifications, however, are known only for the In and T1 halides, similar to the alkali halides and rare-earth monochalcogenides, but no such modifications are reported for the isoelectronic Sn and Pb chalcogenides. 

In these relations S is salinity of the aqueous phase expressed in wt.% NaCl /(A) and 0(A) are function of the alcohol type and concentration they decrease (starting from zero) upon increasing the alcohol content in the system n0E is the average number of ethylene oxide groups per non-ionic SAS molecule k, a, b, c and cr are constants nc is the number of carbon atoms in the alkane forming the oil phase. 

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