License Info
Image Use
Custom Photos
Site Info
Contact Us

Visit Science,
Optics, & You

The Galleries:

Photo Gallery
Silicon Zoo
Chip Shots
DNA Gallery
Amino Acids
Religion Collection
Cocktail Collection
Screen Savers
Win Wallpaper
Mac Wallpaper
Movie Gallery

Dipolar Powder Patterns

The observed NMR spectrum of a solid powder (no MAS, no molecular motion) is the summed signal from crystallites over all possible orientations relative to the applied field Bo. In a system of two spins that are strongly dipolar coupled (relative to J, shift anisotropies, quadrupolar couplings) one will observe a typical dipolar powder pattern as shown below.

Interactive Java Tutorial
Our servers have detected that your web browser does not have the Java Virtual Machine installed or it is not functioning properly. Please install this software in order to view our interactive Java tutorials. You may download the necessary software by clicking on the "Get It Now" button below.


By changing the orientation relative to Bo (set to point along +z) one can visualize how an individual crystallite contributes to the powder pattern. The vertical lines above represent the observed transitions at a particular orientation. All orientations contribute to the observed powder spectrum. All transitions from spin(s) of type specified by Spin 1 are detected. Note what happens at the "magic angle", where q=54.7. Also note how rotations about the +z axis don't affect the spectrum because dipolar interactions are symmetric.


Questions or comments? Send us an email.
© 1995-2022 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, software, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.
Last Modification: Friday, Nov 13, 2015 at 02:19 PM
Access Count Since April 01, 1999: 49311