NMR Experiments and Data Processing
This document describes what types of information is presented in different NMR spectra and how to process the data.
- H-1 NMR Data
- Experimental Description - 300 MHz proton NMR. 90 degree pulse.
- Data Processing
- FID - Baseline Correct, Fourier Transform
- Spectrum - Phase, Zoom, Integrate
- Spectral Interpretation
- Splitting Patterns, indicate number of protons on adjacent carbons.
- Integration, indicates relative number of protons.
- Chemical Shift (ppm), indicates chemical environment.
- C-13 NMR Data
- Experimental Description - 75 MHz Carbon NMR.
- Data Processing
- FID - Baseline Correct, Exponential Multiply (Line Broadening ca 2), Fourier Transform
- Spectrum - Phase, Zoom, Peak Picking
- Spectral Interpretation
- Chemical Shift (ppm), indicates chemical environment.
- These are decoupled spectra so no splitting information is present.
- Notice solvent peak (CDCl3) at ca 77 ppm.
- Quaternary carbon's frequently give small peaks.
- Acquisition conditions NOT optimized for integration
- DEPT 45 NMR Data
- Experimental Description - DEPT 45, Distortionless Enhancement of Polarization Transfer using a 45 degree decoupler pulse.
- Data Processing
- FID - Baseline Correct, Exponential Multiply (Line Broadening ca. 2) Fourier Transform
- Spectrum - Phase, Zoom, Peak Pick
- Spectral Interpretation - This pulse sequence produces a carbon spectrum containing only carbons with protons attached (quaternary carbons are not observed).
- DEPT 90 NMR Data
- Experimental Description - DEPT 90, Distortionless Enhancement of Polarization Transfer using a 90 degree decoupler pulse.
- Data Processing
- FID - Baseline Correct, Exponential Multiply (Line Broadening ca. 2) Fourier Transform
- Spectrum - Phase, Zoom, Peak Pick
- Spectral Interpretation - This pulse sequence produces a carbon spectrum containing only carbons with an even number of protons attached. Methene, CH3
- DEPT 135 NMR Data
- Experimental Description - DEPT 135, Distortionless Enhancement of Polarization Transfer using a 135 degree decoupler pulse.
- Data Processing
- FID - Baseline Correct, Exponential Multiply (Line Broadening ca. 2) Fourier Transform
- Spectrum - Phase (use same phase correction as DEPT 45 experiment), Zoom, DC Offset to observe inverted peaks, Peak Pick.
- Spectral Interpretation - - This pulse sequence produces a carbon spectrum with methyl (CH3) and methyne (CH) carbons are up. Methene (CH2) carbons are down.
- COSY NMR Data
- Experimental Description - 2D Corelation Spectroscopy Experiment.
- Data Processing - 2D Processing Required. This is only available with the 2D license for NUTS. If you have this license you can use this macro to process the raw data file. You should read the header information for details. If you do not have access to the 2D version of NUTS, you may view the processed data as a gif figure.
- Spectral Interpretation - The COSY spectrum plots proton vs proton. The 1D spectrum is plotted along each axis. The 2D data consists of the matrix diagonal(not very useful), and the cross peaks. These peaks show which protons (from the diagonal) are coupled.
- HETCOR NMR Data
- Experimental Description - 2D Heteronuclear correlation spectroscopy.
- Data Processing - 2D Processing Required. This is only available with the 2D license for NUTS. If you have this license you can use this macro to process the raw data file. You should read the header information for details. If you do not have access to the 2D version of NUTS, you may view the processed data as a gif figure.
- Spectral Interpretation - The HETCOR spectrum plots proton vs carbon. The 1D spectra are displayed along the appropriate axis. The 2D peaks show which protons are coupled to which carbons.
This page is maintained by
Scott Van Bramer
Department of Chemistry
Widener University
Chester, PA 19013
Please send any comments, corrections, or suggestions to
svanbram@science.widener.edu.
This page has been accessed
times since 1/5 /96 .
Last Updated 1/5/96