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Updated: Jul 19, 2026
09:13
Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
Isolation and structure of higher diamondoids, nanometer-sized diamond molecules
J E Dahl1, S G Liu, R M K Carlson
1MolecularDiamond Technologies, ChevronTexaco Technology Ventures, Post Office Box 1627, Richmond, CA 94802, USA.
Science (New York, N.Y.)
|December 3, 2002
Summary
Higher diamondoids, large molecules with unique shapes and stability, were isolated from petroleum. These diamond-crystal cage structures offer potential as advanced nanometer-scale building blocks.
Area of Science:
- Materials Science
- Organic Chemistry
- Nanotechnology
Background:
- Petroleum contains complex hydrocarbon structures.
- Diamondoids are cage-like molecules with exceptional thermal stability.
Purpose of the Study:
- To isolate and characterize higher diamondoids (C22+) from petroleum.
- To explore their potential as molecular building blocks.
Main Methods:
- Isolation and crystallization techniques applied to petroleum fractions.
- Single-crystal X-ray diffraction for structural determination.
Main Results:
- Successfully isolated diamondoids with 4 to 11 diamond-crystal cages.
- Determined crystal structures for representatives of three diamondoid families.
- Observed diverse 3D shapes, including chiral forms, and multiple derivatization sites.
Conclusions:
- Higher diamondoids possess valuable properties like rigidity, strength, and diverse molecular architectures.
- These characteristics make them promising candidates for nanometer-scale molecular engineering and materials science applications.
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