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- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/06%3A_The_Periodic_Table/6.16%3A_IonThis page explains the northern lights, which are produced by charged particles (ions) interacting with Earth's magnetic field. Ions form when atoms gain or lose electrons during electron transfer, re...This page explains the northern lights, which are produced by charged particles (ions) interacting with Earth's magnetic field. Ions form when atoms gain or lose electrons during electron transfer, resulting in positive or negative charges. These reactive ions can combine to create neutral compounds and are influenced by magnetic fields, as illustrated by the northern lights phenomenon.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/19%3A_Nuclear_Magnetic_Resonance_Spectroscopy/19.02%3A_Environmental_Effects_on_NMR_SpectraIn this section we will consider why the location of a nucleus within a molecule—what we call its environment—might affect the frequency at which it absorbs and why a particular absorption line might ...In this section we will consider why the location of a nucleus within a molecule—what we call its environment—might affect the frequency at which it absorbs and why a particular absorption line might appear as a cluster of individual peaks instead of as a single peak.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/14%3A_Nuclear_Magnetic_Resonance_Spectroscopy/14.05%3A_Chemical_Shifts_Depend_upon_the_Chemical_Environment_of_the_NucleusThis page discusses the chemical shift in NMR, which reveals information about the local molecular structure by measuring the local magnetic field around a nucleus, affected by electron currents and q...This page discusses the chemical shift in NMR, which reveals information about the local molecular structure by measuring the local magnetic field around a nucleus, affected by electron currents and quantified by the shielding constant. It operates on a delta scale and includes contributions from local (diamagnetic and paramagnetic) and molecular factors (magnetic susceptibility from neighboring groups).
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/19%3A_Nuclear_Magnetic_Resonance_Spectroscopy/19.03%3A_NMR_SpectrometersEarlier we noted that there are two basic experimental designs for recording a NMR spectrum. One is a continuous-wave instrument in which we scan through the range of frequencies over which the nucleu...Earlier we noted that there are two basic experimental designs for recording a NMR spectrum. One is a continuous-wave instrument in which we scan through the range of frequencies over which the nucleus of interest absorbs, exciting them sequentially. Most instruments use pulses of RF radiation to excite all nuclei at the same time and then use a Fourier transform to recover the signals from the individual nuclei. Our attention in this chapter is limited to instruments for FT-NMR.
- https://chem.libretexts.org/Courses/Western_Washington_University/Biophysical_Chemistry_(Smirnov_and_McCarty)/05%3A_Nuclear_Magnetic_Resonance_(NMR)_Spectroscopy_-_Introduction/5.05%3A_Effects_of_the_Sample_Equipment_and_Recording_Regimes_on_the_NMR_Spectral_Sensitivity_and_Resolution.This Chapter describes how key elements of NMR data collection (properties of sample molecules, their concentration, magnet strength B0, recording regimes) affect the two fundamental qualities of the ...This Chapter describes how key elements of NMR data collection (properties of sample molecules, their concentration, magnet strength B0, recording regimes) affect the two fundamental qualities of the recorded data: spectral resolution and spectral sensitivity.
- https://chem.libretexts.org/Courses/Western_Washington_University/Biophysical_Chemistry_(Smirnov_and_McCarty)/05%3A_Nuclear_Magnetic_Resonance_(NMR)_Spectroscopy_-_Introduction/5.03%3A_Chemical_shift_in_units_of_Hz_and_ppmThis Chapter introduces the other most common unit to measure and report the NMR resonance frequency: ppm, parts-per-million. We will consider examples when the frequency units of Hz (1/second) are th...This Chapter introduces the other most common unit to measure and report the NMR resonance frequency: ppm, parts-per-million. We will consider examples when the frequency units of Hz (1/second) are the most justified choice and the opposite cases- when ppm???s should be used. We will also start describing quantitatively how raw NMR signal, S(t), depend on time t, initial current S0, and two properties of the target nucleus: resonance frequency ?? (or ??) and relaxation rate R.
