high-field spectrometer. In a similar fashion, it is possible to upscale the effect of J-coupling relative to the chemical shift using pulse sequences that include additional J-coupling evolution periods interspersed with conventional spin evolutions. Other chemical shifts The Knight shift (first reported in 1949) and Shoolery's rule are observed with pure metals and methylene groups, respectively. The NMR chemical shift in its present-day meaning first appeared in journals in 1950. Chemical shifts with a different meaning appear in X-ray photoelectron spectroscopy as the shift in atomic core-level energy due to a specific chemical environment. The term is also used in Mössbauer spectroscopy, where similarly to NMR it refers to a shift in peak position due to the local chemical bonding environment. As is the case for NMR the chemical shift reflects the electron density at the atomic nucleus. See also EuFOD, a shift agent MRI Nuclear magnetic resonance Nuclear magnetic resonance spectroscopy of carbohydrates Nuclear magnetic resonance spectroscopy of nucleic acids Nuclear magnetic resonance spectroscopy of proteins Protein NMR Random coil index Relaxation (NMR) Solid-state NMR TRISPHAT, a chiral shift reagent for cations Zeeman effect References External links chem.wisc.edu BioMagResBank NMR Table Proton chemical shifts Carbon chemical shifts Online tutorials (these generally involve combined use of IR, 1H NMR, 13C NMR and mass spectrometry) Problem set 1 (see also this link for more background information on spin-spin coupling) Problem set 2 Problem set 4 Problem set 5 Combined solutions to problem set 5 (Problems 1–32) and (Problems 33–64) Nuclear chemistry Nuclear physics Nuclear magnetic resonance spectroscopy pl:Spektroskopia NMR#Przesunięcie chemiczne