Deuterium and Shift Calculation
dic 2012 · NMR Basic Principles and Progress Libro 23 · Springer Science & Business Media
Libro electrónico
263
Páginas
reportLas calificaciones y opiniones no están verificadas. Más información
Acerca de este libro electrónico
In 1931 Vrey, Brickwedde, and Murphy discovered the hydrogen isotope deuterium. The isotopic enrichment was found to arise from the fact that the electrolysis oflight water is faster than of heavy water [1,2]. This success showed that although different isotopes of an element behave identically from a chemical standpoint the different isotopic masses nevertheless lead to both isotope effects on equilibrium as well as on rate constants of chemical reactions. Soon, ratios of equilibrium constants of isotopic reactions were called "equilibrium isotope effects" (EIE), ratios of isotopic rate constants "kinetic isotope effects" (KIE). Isotope effects have been found to be especially large for those elements which are directly involved in bond breaking and bond formation during the reaction studied [3]. Such effects are, therefore, referred to as "primary". Isotopic substitution in atomic sites which maintain all chemical bonds with their neighbors during the reaction of interest leads then only to smaller "secondary" isotope effects. Because of the unique mass relation between the different hydrogen isotopes hydrogen/deuterium isotope effects are particularly large and have attracted most attention. The largest contributions to these effects arise from changes in the vibrational frequencies of the reactants. The theory of equilibrium isotope effects has been founded by Vrey [4] and Bigeleisen [5,6] and has widely been accepted [3].
Califica este libro electrónico
Cuéntanos lo que piensas.
Información de lectura
Smartphones y tablets
Instala la app de Google Play Libros para Android y iPad/iPhone. Como se sincroniza de manera automática con tu cuenta, te permite leer en línea o sin conexión en cualquier lugar.
Laptops y computadoras
Para escuchar audiolibros adquiridos en Google Play, usa el navegador web de tu computadora.
Lectores electrónicos y otros dispositivos
Para leer en dispositivos de tinta electrónica, como los lectores de libros electrónicos Kobo, deberás descargar un archivo y transferirlo a tu dispositivo. Sigue las instrucciones detalladas que aparecen en el Centro de ayuda para transferir los archivos a lectores de libros electrónicos compatibles.
