Deuterium and Shift Calculation
Des 2012 · NMR Basic Principles and Progress Buku 23 · Springer Science & Business Media
eBook
263
Halaman
reportRating dan ulasan tidak diverifikasi Pelajari Lebih Lanjut
Tentang eBook ini
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].
Beri rating eBook ini
Sampaikan pendapat Anda.
Informasi bacaan
Smartphone dan tablet
Instal aplikasi Google Play Buku untuk Android dan iPad/iPhone. Aplikasi akan disinkronkan secara otomatis dengan akun Anda dan dapat diakses secara online maupun offline di mana saja.
Laptop dan komputer
Anda dapat mendengarkan buku audio yang dibeli di Google Play menggunakan browser web komputer.
eReader dan perangkat lainnya
Untuk membaca di perangkat e-ink seperti Kobo eReaders, Anda perlu mendownload file dan mentransfernya ke perangkat Anda. Ikuti petunjuk Pusat bantuan yang mendetail untuk mentransfer file ke eReaders yang didukung.
