Search results for "Earth's field NMR"

13C-Decoupled J-Coupling Spectroscopy Using Two-Dimensional Nuclear Magnetic Resonance at Zero-Field

2017

We present a two-dimensional method for obtaining 13C-decoupled, 1H-coupled nuclear magnetic resonance (NMR) spectra in zero magnetic field using coherent spin-decoupling. The result is a spectrum determined only by the proton–proton J-coupling network. Detection of NMR signals in zero magnetic field requires at least two different nuclear spin species, but the proton J-spectrum is independent of isotopomer, thus potentially simplifying spectra and thereby improving the analytical capabilities of zero-field NMR. The protocol does not rely on a difference in Larmor frequency between the coupled nuclei, allowing for the direct determination of J-coupling constants between chemically equivalen…

Nuclear Magnetic Resonance and Electron Spin Resonance Spectroscopy

2001

The article contains sections titled: 1. Introduction 2. Principles of Magnetic Resonance 2.1. Nuclear and Electronic Properties 2.2. Nuclei and Electrons in a Stationary Magnetic Field 2.3. Basic Principles of the NMR and ESR Experiments 2.4. Relaxation 3. High-Resolution Solution NMR Spectroscopy 3.1. The NMR Experiment 3.1.1. Continuous Wave Methodology 3.1.2. Fourier Transform Methodology 3.2. Spectral Parameters 3.2.1. Chemical Shift 3.2.2. Spin - Spin Coupling 3.2.3. Signal Intensity 3.2.4. Relaxation Times 3.3. NMR and Structure 3.3.1. Hydrogen (1H and 2H) 3.3.2. Carbon (13C) 3.3.3. Fluorine (19F) 3.3.4. Phosphorus (31P) 3.3.5. Nitrogen (14N and 15N) 3.3.6. Oxygen (17O) 3.3.7. Silico…

Nuclear magnetic resonance at millitesla fields using a zero-field spectrometer

2016

We describe new analytical capabilities for nuclear magnetic resonance (NMR) experiments in which signal detection is performed with chemical resolution (via spin-spin J couplings) in the zero to ultra-low magnetic field region, below 1μT. Using magnetic fields in the 100μT to 1mT range, we demonstrate the implementation of conventional NMR pulse sequences with spin-species selectivity.

Billion-Fold Enhancement in Sensitivity of Nuclear Magnetic Resonance Spectroscopy for Magnesium Ions in Solution

2014

Beta-nuclear magnetic resonance (NMR) spectroscopy is highly sensitive compared to conventional NMR spectroscopy, and may be applied for several elements across the periodic table. Beta-NMR has previously been successfully applied in the fields of nuclear and solid-state physics. In this work, beta-NMR is applied, for the first time, to record an NMR spectrum for a species in solution. 31Mg b-NMR spectra are measured for as few as 10^7 magnesium ions in ionic liquid (EMIM-Ac) within minutes, as a prototypical test case. Resonances are observed at 3882.9 and 3887.2 kHz in an external field of 0.3 T. The key achievement of the current work is to demonstrate that beta-NMR is applicable for the…

ChemInform Abstract: Electron-Correlated Approaches for the Calculation of NMR Chemical Shifts

2010