[extropy-chat] Buckyballs to the rescue

Amara Graps amara at amara.com
Mon Mar 8 11:04:42 UTC 2004


Robert Bradbury:
>Actually, I'm reasonably certain you can find C60 in soot from a
>fire that is hot enough (though others may want to check this...).
>So if the alchemists had had electron microscopes they might have
>discovered it.  Given that they didn't C60 may have simply been an
>unknown component of carbon black.

Reminder: probably in space too, see the note below, that I sent to
the extropians list last October.

As a follow-up to the note below, Rotundi and coauthors have
the following paper in press to the journal:

Fullerenes, Nanotubes and Carbon Nanostructures.

Here is that new paper:

C60 AND GIANT FULLERENES IN SOOT CONDENSED IN VAPORS WITH
VARIABLE C/H2 RATIO
by
Frans J.M. Rietmeijer,
Alessandra Rotundi,
Dieter Heymann,

Abstract: A transmission electron microscope study of individual
soot grains forming fluffy carbon particles produced using the
arc-discharge technique revealed close-packed arrangements of single
-wall ring structures with average diameters of 0.7, 1.1, 3.0, 5.5
and 8.2 nanometers. These structures were hypothesized to be C60 and
giant, C540, C960 and C1500, fullerenes that could form by
coalescence during condensation and soot agglomeration although in
situ solid-state growth cannot be excluded. Mass spectroscopy and
HPLC chromatography of the samples confirmed the presence of C60
fullerene in all samples giving confidence to the giant fullerene
growth scenario. Our results suggest that fullerenes could be common
in soot grains produced by this technique as well as being an
important carbon phase among in C-rich accretion disks around young
stellar objects and among the dust in the interstellar medium.

======= sent 21 October 2003 to extropians (couldn't find it in 
archives though)

To:  Extropy-chat at extropy.org
From: Amara Graps <amara at amara.com>
Subject: Buckyballs in space

Last Spring, the extropians list (I think) had a discussion
regarding organized carbon materials in space. Along that vein, I
present something I read at a recent planetary science conference.
Alessandra Rotundi had a poster there about buckyballs formed in
interplanetary dust particles.

V Convegno di Scienze Planetarie, Gallipoli, Italy
September 15-19, 2003
http://www.fisica.unile.it/astro/planetologia/

Soot Analogs: It Should be a Metastable Carbon

by A. Rotundi, F.J.M. Rietmeyer, D. Heymann, V. Mennella, L. Colangeli

 From the poster:

{begin quote}
The search for C60 among IS and circumstellar dust, including the
solar nebula as enclosed in meteorites and IP dust particles (IDPs)
has not yet produced unambiguous results. Yet He and Ne associated
with carbon materials require efficiet trapping sites, e.g.
nanotubes or fullerenes (1). A carbon X-ray Absorption Near Edge
Spectroscopy (C-XNES) study of the carbon-rich IDP L2008F4 showed a
peak at 286.3 eV possibly due to C60 (2). As part of the long-term
program to identify carbon spectral signatures in astrophysical
settings, a detailed study of condensed carbon showed nanotubes,
carbon onions and soot grains froming fluffy claim-like aggregates
(CLA) (3). High-resolution Transmission Electron Microscope (HRTEM)
observations showed that CLA grains consist of densely packed
single-wall spheres. The smallest ones are identified as C60, whose
presence is confirmed by mass spectroscopy and High Performance
Liquid Chromatography (HPLC). The larger ones we submit are giant
fullerenes forming protofringes, in individual soot grains, suggest
post-condensation adjustment, i.e. incipient fullerene
crystallization.

(1) Palma R.L. et all (2001) LPS XXXII, CDROM #2074,
(2) Bajt, S. et al (1996( LPS XXVII, #5758
(3) Rotundi, A. et al (1998) A & A 329, 1087-1096.
{end quote}


-- 

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Amara Graps, PhD          email: amara at amara.com
Computational Physics     vita:  ftp://ftp.amara.com/pub/resume.txt
Multiplex Answers         URL:   http://www.amara.com/
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"Oh you damned observers, you always find extra things."
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