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The Effect of O2 Intercalation on the Rotational Dynamics and the Ordering Transition of C60

Published online by Cambridge University Press:  15 February 2011

S. A. Myers
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185-0367
R. A. Assink
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185-0367
J. E. Schirber
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185-0367
D. A. Loy
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185-0367
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Abstract

We have used 13C magic-angle spinning (MAS) nuclear magnetic resonance (NMR) to characterize the structure and rotational dynamics of C60 containing oxygen molecules located in the interstitial sites of the fcc lattice. Under normal conditions, a narrow peak at 143.7 ppm is observed for C60. When exposed to oxygen at moderate pressures, several additional resonances appear in the 13C MAS NMR spectrum. These secondary resonances are shifted downfield from the main peak at 143.7 ppm and are due to the Fermi-contact interaction of the paramagnetic oxygen molecules with the 13C nuclear spins. The presence of oxygen depresses the orientational ordering transition by ca. 20 K as observed by DSC. The spin-lattice relaxation time (T1) of each secondary peak shows a minimum near the ordering transition, indicating that this transition is not dependent on the number of oxygen molecules surrounding an individual C60 molecule. The T1 due to paramagnetic relaxation, normalized by the number of surrounding oxygen molecules, is constant. This observation demonstrates that within a given sample, the dynamics of C60 molecules are independent of the number of surrounding oxygen molecules.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

REFERENCES

1. Assink, R. A., Schirber, J. E., Loy, D. A., Morosin, B., and Carlson, G. A., J. Mater. Res. 7, 2136 (1992).Google Scholar
2. Schirber, J. E., Assink, R. A., Samara, G. A., Morosin, B. and Loy, D. A., Phys. Rev. B (in press).Google Scholar
3. Samara, G. A., Hansen, L. V., Assink, R. A., Morosin, B., Schirber, J. E., and Loy, D. A., Phys. Rev. B 47, 4756 (1993).Google Scholar
4. Johnson, R. D., Bethune, D. S., and Yannoni, C. S., Acc. Chem. Res. 25, 169 (1992).Google Scholar
5. Jesson, J. P., in The Paramagnetic Shift, edited by Mar, G. N. La, De, W. Horrocks, W., J., , and Holm, R. H. (Academic Press, New York, 1973), pp. 152.Google Scholar
6. Carrington, A. and McLachlan, A. D., Introduction to Magnetic Resonance (Harper & Row, New York, 1967).Google Scholar
7. Belahmer, Z., Bernier, P., Firlej, L., Lambert, J. M., and Ribet, M., Phys. Rev. B., 47, 15980 (1993).Google Scholar
8. Dereux, F., Boilot, J. P., Chaput, F., and Sapoval, B., Phys. Rev. Lett. 65, 614 (1990).Google Scholar
9. Satterlee, J. D., in Annual Reports on NMR Spectroscopy, Vol. 17 (Academic Press Inc., London, 1986)pp. 149.Google Scholar