In Situ NMR Methods in Catalysis
Title | In Situ NMR Methods in Catalysis PDF eBook |
Author | Joachim Bargon |
Publisher | Springer Science & Business Media |
Pages | 179 |
Release | 2007-05-15 |
Genre | Science |
ISBN | 354071426X |
Achemist,facedwiththeproblemofdeterminingthemechanismofachemical reaction, tries to identify a set of reactions that will account for the observed behavior:Ideally,asmallsetofknownreactionsshoulddescribeingreatdetail exactly what takes place at each stage of a chemical transformation. The fact that many reactions proceed in a stepwise fashion can most convincingly be demonstrated if intermediate species can be isolated and shown to proceed to the same products under otherwise identical reaction conditions. An - termediate is the reaction product of each of these steps, except for the last onethatformsthe?nalproduct. Someintermediatesarestablecompoundsin theirownright;someothers,however,aresoreactivethattheirisolationisnot possible. Occasionally, evidence for the existence of short-lived intermediates may be obtained, in particular by spectroscopic observation. The latter may - low a direct observation or an indirect inference from unusual phenomena occurring in the reaction products during in situ investigations of their c- responding chemical reactions. In NMR spectroscopy, for example, transient emissionandenhanced absorptionlinesmaybeobserved, andoneisinclined to believe that there is a universal and unambiguous reason for their appe- ance. Thisisnotnecessarilythecase,however,sincethisseeminglyidentical phenomenon may have a strikingly different origin: During free radical re- tions,aphenomenoncalledchemicallyinduced dynamicnuclear polarization (CIDNP) may give rise to virtually the same effect as occasionally observed duringhomogeneous(andpossiblyevenheterogeneous)hydrogenations:The latter phenomenon, called parahydrogen-induced polarization (PHIP), has a completely different physical basis. It was ?rst noticed twenty years later than CIDNP and occurs if there is an imbalance of the two spin isomers of symmetric molecules such as dihydrogen when hydrogenating unsaturated compoundsusingappropriatecatalysts. Thesetwoeffects,ifnotdifferentiated properly, can cause misinterpretations of reaction mechanisms, as occurred initially when their different origins had not yet been understood approp- ately.
NMR Techniques in Catalysis
Title | NMR Techniques in Catalysis PDF eBook |
Author | Alexis T. Bell |
Publisher | CRC Press |
Pages | 450 |
Release | 1994-02-25 |
Genre | Science |
ISBN | 9780824791735 |
This volume provides an overview of the applications of modern solid-state nuclear magnetic resonance (NMR) techniques to the study of catalysts, catalytic processes, species adsorbed on catalysts and systems relevant to heterogeneous catalysis. It characterizes the structure of catalytic materials and surfaces.
NMR and MRI of Electrochemical Energy Storage Materials and Devices
Title | NMR and MRI of Electrochemical Energy Storage Materials and Devices PDF eBook |
Author | Yong Yang |
Publisher | Royal Society of Chemistry |
Pages | 573 |
Release | 2021-06-21 |
Genre | Science |
ISBN | 1788018486 |
The aim of this book is to introduce the use of NMR and MRI methods for investigating electrochemical storage materials and devices to help both NMR spectroscopists entering the field of batteries and battery specialists seeking diagnostic methods for material and device degradation.
Characterization of Heterogeneous Catalysts
Title | Characterization of Heterogeneous Catalysts PDF eBook |
Author | Francis Delannay |
Publisher | Marcel Dekker |
Pages | 432 |
Release | 1984 |
Genre | Science |
ISBN |
NMR Techniques in Catalysis
Title | NMR Techniques in Catalysis PDF eBook |
Author | Alexis T. Bell |
Publisher | CRC Press |
Pages | 447 |
Release | 2020-07-24 |
Genre | Science |
ISBN | 1000105083 |
This volume provides an overview of the applications of modern solid-state nuclear magnetic resonance (NMR) techniques to the study of catalysts, catalytic processes, species adsorbed on catalysts and systems relevant to heterogeneous catalysis. It characterizes the structure of catalytic materials and surfaces.
In-situ Spectroscopic Studies of Adsorption at the Electrode and Electrocatalysis
Title | In-situ Spectroscopic Studies of Adsorption at the Electrode and Electrocatalysis PDF eBook |
Author | Shi-Gang Sun |
Publisher | Elsevier |
Pages | 559 |
Release | 2011-08-11 |
Genre | Science |
ISBN | 0080489060 |
In-Situ Spectroscopic Studies of Adsorption at the Electrode and Electrocatalysis is a new reference on in-situ spectroscopic techniques/applications, fundamentals of electrocatalysis at molecule level, and progresses within electrochemical surface science. Presenting both essential background knowledge at graduate level and original research within the fields of spectroscopy, electrochemistry, and surface science. Featuring 15 chapters by prominent worldwide scholars, based on their recent progress in different aspects of in-situ spectroscopy studies, this book will appeal to a wide audience of scientists. In summary this book is highly suitable for graduates learning basic concepts and advanced applications of in-situ spectroscopy, electrocatalysis and electrode adsorptions.* Written by the most active scientists in the fields of spectroscopy, electrochemistry and surface science* Essential background knowledge for graduate students* A modern reference of cutting-edge scientific research
In-situ Spectroscopy in Heterogeneous Catalysis
Title | In-situ Spectroscopy in Heterogeneous Catalysis PDF eBook |
Author | James F. Haw |
Publisher | Wiley-VCH Verlag GmbH |
Pages | 296 |
Release | 2002 |
Genre | Science |
ISBN |
"Not using in-situ methods to examine catalytic processes is like studying a life with access only to the prenatal and postmortem states." This quote from the world renowned specialist in the field of in situ methods, Gabor A. Somorjai, clearly emphasizes the importance of these techniques in understanding heterogeneous catalysis - a type of chemical reaction used nowadays for most chemically produced supplies and fuels. Yet the fundamental mechanisms are often still not completely understood. Many of the leading scientists in the field have contributed to this book which provides an overview of the most varied spectroscopic and related methods for studying catalytic structures and their functions during a chemical reaction. While primarily written for users of these methods, this is also a valuable aid to interpreting the phenomena observed. Indispensable for everyone working in the field.