Applications to Inorganic Materials

The curves clearly illustrate the presence of an increasingly large exothermic reaction after the 244°C lattice transition of the ammonium perchlorate. In the 0.1% KC103 region of impurity, the heat evolved after ihe lattice transition was great enough to initiate complete thermal decomposition of the sample. This represents an effective 15(7 lowering of the thermal decomposition temperature of the pure material, which normally decomposes 

For KCI03 (curve 4), the endothermic peak at 375CC corresponds to the 

Rajeshwar et al. (180) used DSC to determine the enthalpy of crystal structure transformations of MC104 salts, where M — Na, K, Rb, Cs, and NH4. As illustrated in Table 7.15, inconsistencies in the literature data are striking, especially with M = Na, K, Rb, and Cs. Most of the earlier studies used DTA techniques to determine the enthalpy changes. However, the literature values for NH4CI04 are in good agreement with the author s results. 

Erdey and Paulik (100), in a simultaneous DTA-TG study, investigated the thermal decomposition of barium, strontium, manganese(II), calcium, magnesium, and zinc oxalates in air and nitrogen atmospheres. It was found that the evolved carbon dioxide formed in the reaction played an important part in that it may inhibit the progress of the reaction and shift the peak temperatures to higher values. 

The changes in enthalpy which occur when CaHP04-2H20 is heated up to 1300°C were determined by a DTA method by Mesmer and Irani (73). An 

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This book is intended to be a self-contained introduction to the background of solid-state NMR, its experimental teehniques and applications to inorganic materials. 

The motivation for this work has been the need to develop a systematic description of structural chemistry that is applicable to inorganic materials. The standard electron-pair bond model of organic chemistry does not work for these compounds, and physical theories tend to be either too simplistic or too complex to be widely useful. 

E. APPLICATIONS TO INORGANIC MATERIALS 1. Alkaline Earth Halide Hydrates... 

In the present discussion we present a brief review of the fundamental equations as well as some of the basic and very important aspects in relation to the Mossbauer isotopes and transitions. Instrumentation and spectral analysis through a routine application of the method, follows in Sect. 7 by some representative applications to inorganic materials. This paper is not intended to be an extensive summary of the literatura data on the problem but aims to indicate what kind of information one can obtain from Mossbauer spectra, especially from those involving Fe, Sn, Te and Sb Mossbauer isotopes. The authors consider the topics discussed here to be of practical interest for chemists and material science engineers. 

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