Molecular elements, characterization data required

Although both the laboratory and industrial scale materials science of catalysts requires an integrated approach as already mentioned above, it is customary to classify the characterization methods by their objects and experimental tools used. I will use the object classification and direct the introductory comments to analysis, primarily elemental and molecular surface analysis, determination of geometric structure, approaches toward the determination of electronic structure, characterization by chemisorption and reaction studies, determination of pore structure, morphology, and texture, and, finally, the role of theory in interpreting the often complex characterization data as well as predicting reaction paths. 

The relatively simple form of the rate law in the Power-Law Formalism has several important implications for the characterization of the molecular elements of the system. In particular, there are known methods for estimating the kinetic parameters and the amount of data required for the estimation is minimal. 

Any product obtained from a chemical process has to be characterized. If the product is a solid, an even larger set of characterization data is required than that required for a liquid or a gas. Liquids and gases are homogeneous on a molecular level and therefore the properties of the bulk are identical to the properties of any volume element larger than a few molecules. A solid can be inhomogeneous, so the properties of any volume element may be different from each other. If products from crystallization processes are considered, the product no doubt should be homogeneous on a medium scale, but it will still be necessary to determine both the intrinsic properties of the solid and the particle shape, particle size, and particle size distribution in addition to the mechanical properties of the solid such as powder flow properties. 

One key aspect of SOMC is the determination of the structure of surface complexes at a molecular level one of the reasons being that our goal is to assess structure-activity relationships in heterogeneous catalysis, which requires a firm characterization of active sites or more exactly active site precursors. While elemental analysis is an essential first step to understand how the organometallic complex reacts with the support, it is necessary to gather spectroscopic data in order to understand what are the ligands and... 

The complexity of quality control for proteins, as compared to small molecules, is most evident in the requirements for proof of structure. Many small molecules can be fully characterized using a few spectroscopic techniques (e.g., NMR, IR, mass spectrometry, and UV) in conjunction with an elemental analysis. However, proving the proper structure for a protein is much more complex because 1) the aforementioned spectroscopic techniques do not provide definitive structural data for proteins, and 2) protein structure includes not only molecular composition (primary structure) but additionally, secondary, tertiary, and, in some cases, quaternary features. Clearly, no single analytical test will address all of these structural aspects hence a large battery of tests is required. 

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