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Chaoite has an hexagonal crystal structure and it 7 was proposed that it consisted of polyyne or polycumulene carbon chains lying parallel to the hexagonal axis. Lattice parameters for some of these carbyne forms are summarked in Table 3.
Table 3. Crystal structure data for some carbvnes Carbyne Chaoite a-carbyne P-carbyne Structurea hex. The hfferent forms of carbynes were assumed to be polytypes with different numbers of carbon atoms in the chains lying parallel to the hexagonal axis and different packing arrangements of the chains within the crystallite.
Heimann et al  proposed that the sizes of the unit cells were determined by the spacing between kinks in extended carbon chains, Fig. A, A kinked polyyne chain model for linear carbynes after  ; B, cyclo C carbyne .
X-ray dimaction peaks were rather broad with coherence lengths as low as 20 nm and this was attributed to rapid quenching. The density of Carbolite 1. Molecular orbital calculations indicate that cyclo C carbyne should be relatively stable and experimental evidence for cyclocarbynes has been found , Fig. Diederich et al  synthesised a precursor of cyclo C and showed by laser flash heating and time-of flight mass spectrometry that a series of retro Diels-Alder reactions occurred leading to cyclo C- 18 as the predominant fi-agmentation pattern.
Diederich has also presented a fascinating review of possible cyclic all-carbon molecules and other carbon-rich nanometre-sized carbon networks that may be susceptible to synthesis using organic chemical techniques . Despite many publications on carbynes, their existence has not been universally accepted and the literature has been characterised by conflicting claims and counter claims [e.
This is particularly true of meteoritic carbynes. An interesting account of the nature of elemental carbon in interstellar dust including diamond, graphite and carbynes was given by Pillinger . Reitmeijer [3 11 has re-interpreted carbyne diffraction data and has concluded that carbynes could be stratified or mixed layer carbons with variable heteroelement content H,O,N rather than a pure carbon allotrope.
In addition to questions over interpretation of difhction data, there are reservations about the stability of carbynes. Lagow et al  note that the condensation of the compound Li-CaC-Br to form carbon chains is potentially explosive.
There is also the possibility of cross-linking between carbyne chains and the nature of the termination of the carbyne chains is unclear. The presumption was that these carbynes were stabilised by nitrile and trifluoromethyl end caps.
For composites of carbynes and alkali metal fluorides produced by reduction of ,fluoropolymers with alkali metal amalgams, it is argued that the alkali metal matrix suppresses cross-linking of the carbyne chains . Despite the scepticism in some quarters, a large number of chemical and physical methods have been developed for producing carbynoid materials.
These include: dehydropolymerisation of acetylene, dehydrohalogenation of polyvinylidene halides and reductive dehalogenation of poly tetrafluoroethy1ene and related compounds, condensation of carbon vapour produced by various means, e. At present, no allcarbon carbynoid material has been isolated in large single crystal form and, consequently, full X-ray structural analyses and bulk property measurements have not been performed. An extensive review of carbynes by Russian workers  was published after this Section of the Chapter was completed.
The C, molecule, Buckminsterfullerene, was discovered in the mass spectrum of laser-ablated graphite in  and crystals of C, were fitst isolated from soot formed from graphite arc electrodes in . Although these events are relatively recent, the C60molecule has become one of the most widely-recognised molecular structures in science and in the codiscoverers Curl, Kroto and Smalley were awarded the Nobel prize for chemistry. Part of the appeal of this molecule lies in its beautiful icosahedral symmetry - a truncated icosahedron, or a molecular soccer ball, Fig.
The C6,, molecule contains 12 pentagons and 20 hexagons. This type of hexagonal-pentagonal structure closely resembles the geodesic domes developed by the architect and engineer R. Buckminster Fuller, after whom the molecule is named. In the C , molecule each carbon atom is bonded to three 10 molecule is named. In the Cbomolecule each carbon atom is bonded to three others by two longer bonds length pm and one shorter bond bond length pm. Tables 1 and 2.
The double bonds lie between two hexagons and are therefore known as bonds whereas the single bonds link a hexagon to a pentagon and are known as bonds. It follows that there is bonding anisotropy in the C,, molecule since bonds around a pentagon are all single bonds and bonds around a hexagon are alternately single bonds and double bonds. It appears therefore that the bonding in C,, is mainly sp2with delocalised 7c electrons, but with some sp3character resulting from curvature of the C-C bonds.
Those grown from solution have a variety of crystal structures depending upon the solvent used, e. Solid state 13C nuclear magnetic resonance, nmr, and other spectroscopic studies show that, despite the bonding anisotropy, all carbon atoms in the C, molecule are equivalent . This is because at room temperature the C,, molecules are re-orienting rapidly on their lattice sites. As the temperature is reduced, there is a phase transition at K to a primitive cubic structure  as a result of orientational ordering of some of the c 6 0 molecules.
At 86K there is a glass transition in which the orientational ordering is frozen [46, Fullerenes are a range of stable closed-shell carbon molecules and their derivatives, of which C,, is the archetype. The next highest stable member of the series is C,, which is found in small quantities with C, in arc electrode soot. C,, may be regarded as a C,, molecule with an extra belt of hexagons inserted at the 11 the stability of Fullerenes and the occurrence of 'magic numbers' in the Fullerene series.
The rule states that closed carbon cages in which the pentagons are isolated from each other are likely to be more stable than those in which pentagons are in contact.
C,, is the smallest closed shell carbon cluster that avoids abutting pentagons and Gois the next smallest.
Mass fragments in the range C,,,C,, detected in mass spectra [52,53] have been amibuted to giant Fullerenes but none has been isolated. As expected from its oblate spheroidal shape a molecular rugby ball , the C,, molecule has lower symmetry than the C, molecule. There are also five different types of C atom sites and eight different types of C-C bond in the C,, molecule. The structural chemistry of C, crystals is also much more complex than for C , crystals.
As the temperature is progressively lowered there is a complex series of transitions to rhombohedral, hexagonal, and monoclinic phases . An excellent monograph on Fullerenes and carbon nanotubes has been published recently [58 1. However, a limited comparison of properties is useful for illustrating the influence of chemical bonding upon the properties of diamond, graphite and BuckminsterfulIerene, C,, Table 4.
Carbynes are omitted from the comparison since insufficient is known of their properties. Table 4. This is reflected in the low melting temperature of C,, compared with diamond and graphite. He says… that there are bowls in the heaven with their con- cave side turned towards us, in which the bright exhalations are gathered and produce flames, which are the stars. For the other stars are farther from the earth and for that reason give less light and heat, whereas the moon, though it is nearer the earth, is borne through a region which is not pure.
Robinson, Heraclitus Toronto Heraclitus, the Rival of Pythagoras the earth and the uppermost heaven, it must comprise both atmospheric air and heavenly fire. According to Aristotle de An.
Aristotle infers the sameness of principle fire and soul from the synonymy of fire and exhalation, on the one hand, and of soul and exhalation on the other. Commentators reject the report as crediting Heraclitus with a Stoic doc- trine. This conclusion is re- inforced by an Orphic imitation of the fragment Clem. West EGPhO ] ca? The verb! It follows that our soul is a bit of the bright soul-exhalation, in effect a particle of the divine soul, which comes from the farthest region of the heavens.
I turn now to B , which has come down to us in three versions: i Stobaeus Ecl. Osborne, Rethinking Early Greek Philo- sophy Ithaca 6: in being exhaled from water, soul either alters in effect forms the entire heavens or joins them. Bollack and H. Powell, A Lexicon to Herodotus, s. In Plato, Crit. The connection of our soul with external exhalation is explained in Sextus Adv.
Diels DG — 11 argued that since Sextus says that we breathe in the encompassing k cor, and since what we actually breathe in is air, the k cor, and therefore the principle itself, must be air; this, as we learn from Sextus Adv. As I have suggested above, however, since in Heraclitus the atmospheric air must be part of dry exhalation, the latter is the substance we breathe. On the early uses of Ghor see S. Polito, The Sceptical Road Leiden Nor is it for nothing that in his report Sextus nowhere mentions air.
In this con- nection I propose to consider the following passage of Aristotle de An. One might ask also, for which reason the soul in air should be better and more immortal than that in living beings.
But if the air breathed in is the same in kind, while soul is made of different parts, etc. Fire is not a convenient example of a breathable substance yet Aristotle repeatedly mentions it along with air. Cherniss ACPPh n. From Numenius fr. In becoming wet the soul grows different from the soul substance, becoming, so to speak, less soul. Clement Strom. For those who be- lieve that the body is called Hades of the soul, as if the soul is deranged and intoxicated in it, draw a close allegory.
Gruppe, Die griechischen Culte und Mythen Leipzig 1. For he [sc. For I myself already heard one of the wise men saying that 4. As the newborn soul of a mortal creature, it is young, alive, and awake, but as a particle of the divine, it is old, dead, and asleep.
Burkert above, n. Zeller, in Zeller-Nestle, Philosophie der Griechen 6, 1. Bywa- ter, Heracliti Ephesii Reliquiae Oxford , fr. Diels, E W. This means that death does not deliver the soul from the impact of bodily wetness. Such a theory would range with the ascetic and cathartic ideas of the Archaic Age, typified in the Orphic and Pythagorean doc- trines of pure life.
Diels, in rejecting this clause. As to young and old, these are not reciprocal on any account. For a recent defence of this attribution see A. Powell ed. London Powell, Lex.
At Strom. For they depart in a womanly manner, longing to live on. For these reasons they let their soul go not pure but carrying its appetites with itself, like weights of lead—save those among them who have become renowned for goodness.
There are also those who die in war still with their appetites, and with them it would make no difference whatsoever if they had died of disease. This idea reappears in Plutarch Rom. For this is a dry and best soul [B ], according to Heraclitus, darting out of the body like lightning out of a 22 As seen by G.
But a soul mingled with the body23 and burdened with the body, such as a heavy and misty exhalation, is hard to kindle and to carry up- wards.
If this is a rare accomplishment, the rest of the souls must be impure in varying degree. As particles of the dry exhala- tion, souls must become attached to different strata of the soul-exhala- tion, and the purer they are, the higher they rise.
Since this is the region of the sun and the stars, arriving there the soul returns thither whence it came, hence recovers its divinity.
This suggests that the two sayings probably belonged together, in which case B 3 is to be understood literally cf. Laks, and G. Most eds. Bernays, Gesammelte Abhandlungen Berlin 1. Empedocles B Dio nysus. But although sim- ilar typologically, these doctrines of course differ in the way they moulded the shared eschatological beliefs. These differences may seem secondary to us, but they were undoubtedly of paramount significance for the proponents of these doctrines.
Borgeaud ed. Heraclitus, the Rival of Pythagoras his doctrine of metempsychosis—cf. Bibliography Alderink, Larry J. Creation and Salvation in Ancient Orphism. Chico, Ca. Baltes, Matthias.
Madrid Fasculus 1, Poetae epici Graeci. Testimonia et fragmenta.