X-Ray powder diffraction, for

Electron crystallography offers an alternative approach in such cases, and here we describe a complete structure determination of the structure of polymorph B of zeolite beta [3] using this technique. The clear advantage of electron microscopy over X-ray powder diffraction for elucidating zeolite structures when they only occur in small domains is demonstrated. In order to test the limit of the structural complexity that can be addressed by electron crystallography, we decided to re-determine the structure of IM-5 using electron crystallography alone. IM-5 was selected for this purpose, because it has one of the most complex framework structures known. Its crystal structure was solved only recently after nine years of unsuccessful attempts [4],... 

McCarthy, G. J. 1988. X-ray powder diffraction for studying the mineralogy of fly ash. In Fly Ash and Coal Conversion By-Products Characterization, Utilization and Disposal. Materials Research Society Symposium Proceedings, 113, 75-86. 

A ternary compound of lanthanum with copper and antimony of the stoichiometric ratio 3 3 4 was identified and studied by means of X-ray analysis by Skolozdra et al. (1993). La3Cu3Sb4 (3) compound was found to have the Y3Au3Sb4 type with the lattice parameter of a = 0.9837 (X-ray powder diffraction). For experimental details, see the Y-Cu-Sb system. 

Early investigations of the PrNiSb compound showed that it had the AlB2-type structure with a = 0.4376, c = 0.4053 (Pecharsky et al., 1983a X-ray powder analysis). For experimental procedure, see ScNiSb. At variance with these data, Hartjes and Jeitschko (1995) suggested a ZrBeSi type structure, a = 0.4375, c = 0.8123 from X-ray powder diffraction. For experimental details, see LaNiSb. 

Hoffman and Jeitschko (1988) established the defect CaBe2Ge2 type structure for TbNi2-xSb2, a = 0.42496, c = 0.9649, X-ray powder diffraction. For the sample preparation, see CeNi2-xSb2. 

The synthesized samples were analyzed by X-ray powder diffraction for qualitative and quantitative phase identification. The unit used was a Philips Model with a vertical goniometer and a scintillation counter, utilizing Ni-filtered CuK radiation. For quantitative phase identification an external standard sample of ot-A O, was used. The percentage crystallization was calculated using thez "averaged peak intensities at 20 =35.2° and 20=47.3° of the reference sample and the peak intensity at 20=23.2° for the sample under study (31). 

However, most of the species MnX2 "6NH, are white powders, and probably contain the cation [Mn(NH3)6]2+ (as do those for n > 7), and this is proved by X-ray powder diffraction for X = Cl, Br, I, C104, SOjF and BF4, which have cubic crystal structures belonging to the CaF2 type. 

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