1
62
B.C. Satishkumar et al.rChemical Physics Letters 307 (1999) 158–162
ably larger than those in the case of the nanoparticles
associated with the formation of nanotube bundles.
Magnetization measurements were carried out on
the aligned nanotube bundles from acetylene–ferro-
cene mixtures Žcorresponding to Fig. 2b., to examine
play an important role in the process of alignment
because of their magnetic nature.
Acknowledgements
the magnetic nature of the iron nanoparticles. A
M–H hysteresis loop with a saturation magnetization
of around 20 emurg was obtained. Considering that
the average particle diameter is small Ž2–13 nm., we
One of the authors ŽBCS. acknowledges CSIR,
New Delhi, for a senior research fellowship.
would expect such a reduction in the value of satura-
tion magnetization, compared to the bulk value Ž222
emurg.. It is noteworthy that the iron nanoparticles
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