Tetragonal structure and

Phase equilibria in Ti-H alloys are sensitive to pressure. A new phase appears in near-eutectoid alloys at P > 20 kbar with a tetragonal structure and hydrogen re-distributed from tetra- to octahedral interstices. 

Thorite and orangite (orange thorite) have a tetragonal structure and are isostructural with zircon. Steady-state spectra under X-ray and laser (337 nm) excitations are connected with REE " ", namely Sm " ", Tb ", Dy " " and Eu ". Reabsorption lines of Nd " have been also detected (Gorobets and Rogojine 2001). Laser-induced time-resolved luminescence enables us to detect Eu " and uranyl emission centers (Eig. 4.70). 

Quaternary rare earth borocarbides LnNi2B2C have been discovered recently that exhibit superconducting transition temperatures (Tcs) between 8 and 17 K.25-27 These compounds adopt a tetragonal structure and... 

The complex K2[Ir(OH)6] can be synthesized by treating Na2[IrCl6] with KOH, and has been characterized by absorption spectroscopy, thermogravimetric analysis and voltage-current curves.464 Cd[Ir(OH)6] possesses a tetragonal structure and serves as a magnetically dilute insulator, while Zn[Ir(OH)6] has a cubic structure and exhibits an anomalous magnetic behaviour.465... 

Another problem with small models is that molecules from the solution (e.g. water) may come in and stabilise tetragonal structures and higher coordination numbers [224]. It is illustrative that very few inorganic con5)lexes reproduce the properties of the blue copper proteins [66,67], whereas typical blue-copper sites have been constructed in several proteins and peptides by metal substitution, e.g. insulin, alcohol dehydrogenase, and superoxide dismutase [66]. This shows that the problem is more related to protection from water and dimer formation than to strain. 

Titanium dioxide occurs naturally as the minerals rutile (tetragonal structure), anatase (tetragonal structure), and brookite (orthorhombic structure). 

When subjected to high pressure certain phosphides and arsenides of metals of Groups IIIB and IVB adopt either the cubic NaCl structure (InP, InAs) or a tetragonal variant of this structure (GeP, GeAs) shown in Fig. 6.1(c) in which there are bonds of three different lengths and effectively 5-coordination. The compounds of Ge and Sn, with a total of nine valence electrons, are metallic conductors. This property is not a characteristic only of the distorted NaCl structure, for SnP forms both the cubic and tetragonal structures, and both polymorphs exhibit metallic conduction. (IC 1970 9 335 JSSC 1970 1 143.)... 

Fig. 6 A projection into (100) of the orthorhombic-I structure. The crosses indicate the atom positions in the tetragonal structure, and the arrows the presumed displacements of these atoms during the transition to orthorhombic [17] (reprinted with permission)...

FIGURE 11.29 Crystal structures af metals. The metals are shawn in their positions in the periodic table. Mn has a cubic structure, Ga an orthorhombic structure, In and Sn a tetragonal structure, and Hg a rhombohedral structure (see Figure 11.15). 

The X-ray examination showed a tetragonal structure and the material was presumably the tetragonal p-modification normally found in such preparations. Mass-loss effusion measurements were made from a platinum Knudsen cell from 671 to 982 K, with good reproducibility. It was observed that a sample of ThCU contaminated with water gave appreciably lower vapour pressures, between those for the anhydrous ThCLt and the decomposition pressure of ThOCl2 (see [1972KNA/MUL]). 

They have the face-centered tetragonal structure and thus obtain a unique property of recording advantage of large coercivity when in room temperature, no matter how small the particles are. Prepared by joint thermolysis in the presence of oleic acid and oleylamine, FE—Pt nanoparticles have a narrow size distribution. After further heating, a protective film is formed on the surface of alloys, which remain about the same size. 

Tin oxide is typically found as tin monoxide (SnO) also called stannous oxide and as tin dioxide (SnOa) or stannic oxide. As shown in Figure I, tin monoxide (stannous oxide) adopts a tetragonal structure and tin dioxide (stannic oxide) has rutile structure (hexagonal sUucture). Starmic oxide can be naturally found as cassiterite. 

P-SiC according to their different structural characteristics. a-SiC (2H polytype) has a tetragonal structure and scalariform appearance on the surface. p-SiC (3C polytype) has a reed-like morphology and lubricous surface. p-SiC has better mechanical and heat-resisting properties than a-SiC. 

Figure 2 The geometry and the singly occupied orbital of Cu(NH3)3(SH)+ for (a) the tetragonal structure and (b) the trigonal structure- ...

It is notable that Cu(NH3)3(SH)", which is a simple model of the type 1.5 Metl21-His azurin mutant has (p = 53-54°. Most probably, the spectral characteristics of the type 1.5 proteins are an effect both of the flattened tetragonal structure and the presence of a fourth strong ligand (in type 1.5 proteins the weak methionine ligand is replaced by a stronger ligand). 

Observed in Al-8Fe-20Si and Al-5Fe-30Si (mass%) alloys, cooled at about 10° C min 8-FcAl4Si2 has tetragonal structure, and it transforms to equilibrium Fe2Al9Si2 phase at 500°C. 

The special crystal orbital can be viewed in sections through several imit cells perpendicular to the (001) plane of the tetragonal structure, and with the spiro atoms flattened out for clarity, as is shown in Fig. 15 (this... 

---