Titanium powder pattern

Powder Patterns. Powder patterns on titanium dioxide were obtained using a North American Philips x-ray machine and a standard powder camera. This work was done by A. Caron. 

Use the chart constructed in Prob. 10-3 to index the first five lines on the powder pattern of a-titanium. With Cu Ka radiation, these lines have the following sin 0 values 0.091, 0.106, 0.117, 0.200, and 0.268. 

The effect of the nature of the synthesis medium has also been considered through the replacement of both titanium precursor and solvent. An organic medium has therefore been used containing titanium isopropoxide as precursor and isopropanol as solvent. In these conditions, two different R = [HF]/[Ti] molar ratios have been studied, i.e. 3 and 4. The corresponding X-ray diffraction powder patterns (not shown) are similar to those obtained from the aqueous medium with a broadening of the X-ray peaks suggesting smaller particle size. Here, the salient point is that the recovered powders are coloured, which is consistent with mixed-valency Ti. Such a point will be discussed later. 

In the X-ray diffraction powder pattern of the R = 3 compound (in aqueous medium) most of main lines fall at similar 26 values as those of TiOF2 published by Vorres and Donohue. These authors successfully synthesized this compound using two different routes hydrolysis of titanium tetrafluoride or titanium trifluorochloride or reaction of aqueous or anhydrous HF with Ti02. The oxyfluoride crystallizes in the Pm-3m space group with a lattice parameter of 3.80 A, and a powder density of 3.06 g.cm with one TiOF2 molecule per unit cell. The crystal structure is built up of comer-sharing Ti(X)g (X = O, F) octahedra, where the O and F atoms are randomly distributed. 

Figure 7a shows the powder XRD pattern of the as-prepared mesostructured titania from titanium butoxide. The mesostructure was collapsed at 400 °C for 5 h, indicated by powder XRD diffraction and adsorption properties. 

FIGURE 7.3 Room temperature XRD patterns of BaTiOj powders prepared with different initial barium/titanium ratios. 

Figure 6. Powder x-ray diffraction pattern of titanium dioxide, anatase phase. The intensity scale is presented in arbitrary units.

Titanium sUicaHte-l is characterized by an X-ray powder diffraction (XRD) pattern typical of orthorhombic MFI-type zeoHte (Pmna space group). Only at low Ti content (x< 0.01) is a monoclinic P2i/n symmetry observed, a phenomenon already observed for the aluminum (ZSM-5 [43]) and boron parent... 

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