Synthesis, characterization, and neutron activation of holmium metallofullerenes

Journal Article · Wed Aug 28 04:00:00 EDT 1996 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja960841z· OSTI ID:380777

Cagle, D W; Thrash, T P; Wilson, L J ^[1]; Alford, M ^[2]; Chibante, L P.F. ^[3]; Ehrhardt, G J ^[4]

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1. Rice Univ., Houston, TX (United States)
2. TDA Research, Wheat Ridge, CO (United States)
3. NanoTechnologies of Texas, Bellaire, TX (United States)
4. Univ. of Missouri, Columbia, MO (United States)

Isolation of the first macroscopic quantities of endohedral holmium metallofullerenes (principally Ho@C{sub 82}, Ho{sub 2}@C{sub 82}, and Ho{sub 3}@C{sub 82} by LD-TOF mass spectrometry) has been accomplished by carbon-arc and preparative HPLC methodologies. The detailed procedure for production and isolation of the metallofullerenes includes a new technique whereby holmium-impregnated electrodes are prepared simply by soaking porous graphite rods in an ethanolic solution of Ho(NO{sub 3}){sub 3}.xH{sub 2}O. Monoisotopic {sup 165}Ho offers a unique combination of advantages for neutron-activation studies of metallofullerenes, and purified samples containing {sup 165}Ho@C{sub 82}, {sup 165}Ho{sub 2}@C{sub 82}, and {sup 165}Ho{sub 3}@C{sub 82} have been activated by high-flux neutron irradiation ({Phi} = 4 x 10{sup 13}n cm{sup -2} s{sup -1}) to generate {sup 166}Ho metallofullerenes, which undergo {beta}{sup -} decay to produce stable {sup 166}Er. Chemical workup of the irradiated samples, followed by re-irradiation, has been used to demonstrate that observed decomposition of holmium metallofullerenes is due mainly to `fast` neutron damage rather than to holmium atom nuclear recoil (E{sub max} = 200 eV). This implies that metallofullerene damage can be minimized by using neutron fluxes with the highest possible thermal component. 60 refs., 4 figs.

• OSTI ID: 380777
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 34 Vol. 118; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
DECOMPOSITION
FULLERENES
HOLMIUM COMPOUNDS
MASS SPECTRA
NEUTRON ACTIVATION ANALYSIS
SEPARATION PROCESSES
SYNTHESIS