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William A. Little (Stanford) and excitonic high temp superconductors,

Phys. Rev. A 134 1416 (1964)
Phys. Rev. B 13 4766 (1976)

Given: The BCS model for coupling fermionic opposite momentum conduction band electrons into bosonic Cooper pairs, then Bose condensation into superconductivity. Classic BCS supercons impose electron couplng by lattice deformation. Atomic nuclei are massive and their displacements are only weakly coupled to electron movement.

Replace phonons (quantized lattice vibriatons characterized by Debye temperature) with excitons (quantized electronic excitations) possessing characteristic energies around 2 eV or 23,000 K. Exciton-mediated electron pairing suggests superconductor critical temperatures exceeding 300 K even under the weakest coupling conditions - a robust, processable room temperature organic superconductor.

Little?s structure was polyacetylene bearing polarizable chromophore side groups. Polyacetylene (doped) would be a normal metal with a single mobile electron per C-H molecular unit. Electrons on separate units BCS couple by interacting with side groups? (C-H into C-R) polarizability (excitons from electron slosh) rather than lattice vibrations (phonons from nucleus slosh).

The 1960s proposal was safely beyond synthesis. There was no way to construct a 100% derivatized 100% conjugated polymer backbone. Chromophores could be polycyclic aromatic hydrocarbons or, better, laser dyes; anthraquinone dyes, annelated vat dyes, indanthrene dyes... transition metal complex, Kreutz-Taube ion... A repeated chromophore along the chain would beget a high temp supercon. A chromophore redox gradient would be a supercon diode. A Y-junction would be a supercon transistor. Other molecular devices (e.g., quantum wells) suggest themselves. Pendant group-mediated solubility is not unreasonable.

Such syntheses are now trivially achievable. R is the chromophore. The entirely reasonable monomer is

H2C=C(R)-C(R)=CH2

Grubbs' olefin metathesis extrudes H2C=CH2 gas and Little's proposal is suddenly resident in Pyrex to high molecular weight. Monomer and polymer stereochemistries are implicit. Olefin metathesis is extremely tolerant of unrelated chemical functionality. R may be further elaborated after synthesis. Hydrophobic stacking or hydrogen bonding of chosen chromophores (perhaps plus adjunct small molecules) may access spontaneously ordered 2-D and 3-D lattices.

It is a nice undergraduate independent study project.


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Nice graduate level project too.


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I wrote to Grubbs at Caltech. His office at Moo U in the late 60s was opposite the T-60 NMR room. Folks on both sides of that corridor have gone places. No reply as yet.

Little's proposal has been debated and dismissed on paper. Nobody has tried it. Theory predicts what it is told to predict. If Little had theoretical basis for his proposal sufficient to pass peer review, we should honor it by doing the now cheap and easy experiment.

It's not a big deal. Polycyclic aromatic aldehyde in the benzoin condensation, oxidize to the benzil (e.g., with nitric acid), methylenate both carbonyls. The aldehydes are obtained by oxidizing methyl aromatics or formylating the parent hydrcarbons. Trivial. Yields will be high in every step.

H2C=C(R)-C(R)=CH2 goes to

[=C(R)-C(R)=]n + H2C=CH2

with very large "n." It's a living polymer system. Cap the living end with a sulfur and it spontaneously bonds to a gold surface like densely packed grass, sticking straight up. Why go to all that hassle for a conductivity test?

The simple test is merely a magnet and the Meissner effect. If the goo shoots out of the pot when brought near a magnet, bingo.

If all the HOMO electrons are Cooper-pair condensed, there will be no accessible chemistry. No electron can be diddled unless they all are. The stuff will have astounding physical properties until as a whole pushed out of its superconducting state.

Enviro-whiners will scream about "persistence."


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Quote:
Originally posted by Uncle Al:
Little's proposal has been debated and dismissed on paper. Nobody has tried it. Theory predicts what it is told to predict. If Little had theoretical basis for his proposal sufficient to pass peer review, we should honor it by doing the now cheap and easy experiment.
Peer review is a wonderful thing. It helps to keep a lot of junk out of the journals.

That said--
His 1964 PRA paper has been cited 840 times, including 16 times in 2005. The 1976 paper has been cited 65 times--including some in 2005. This is hardly a dead subject.

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The only problem is that the BCS theory is wrong. It cannot explain how a superconductor can expel an electric field while a current is flowing through it. An absence of scattering is not enough to cancel an electric field; as is well demonstrated by electrons flowing through a vacuum diode. Little's model has the same defect.
The only charge carrier arrangement in a metal that can cancel the applied field while a current is flowing is a Wigner-crystal with a high enough density. The electrons can then tunnel coherently while at the same time acting as a perfect dielectric.

Nonetheless, organic materials might be the correct way to go in order to get room temperature superconduction "within" a material. My studies indicate that SC could be occurring along the strands of the DNA molecule. Note that I am NOT saying that it does!

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Thanks for the citation count! Little's conservative conclusions are so outrageous that folks are strongly motivated to find the error in his reasoning. A 23,000 K Tc dropped by two orders of magnitude is 230 K. Dry Ice sublimates at 195 K. I am strongly motivated to make the stuff and look,

http://www.mazepath.com/uncleal/suprcon2.htm

Supercon theory is non-predictive for composition or lattice structure. Experience suggests desirable unit cell electron counts in metallic BCS supercons. Despite decades of work, theory and practice, MgB2 with an "impossible" Tc over 30 K was stumbled upon (and not improved).

A polarizable third body Cooper-pairs opposite momentum spin-1/2 electrons into composite spin-zero bosons that degenerately condense into the supercon state. BCS supercons use lattice phonons. High temp ceramic supercons are guesswork given no apparent isotope effect (not phonons). Supercon properties like Tc change with external pressure, internal pressure from doping, and lattice configuration and dimensionalty, especially for organic supercons. TTF-counterion supercons are tuned by counterion size.

Nobody has a Dry Ice supercon much less a room temp one. The commercial potential is awesome. Consider medical MRI with mechanical refrigeration isenad of liquid helium. That alone will make you rich.

Theory can predict anything - directly or by sneaking up as perturbation series or Yukawa potentials. Anything reasonable must be reduced to practice to truly know.

Synthesis of Little's fully substituted polyacetylenes appears to be facile in 2006 given olefin metathesis. The starting monomers look ridiculously easy to obtain, though that could have one boojum. If the boojum appears it has workarounds.

I've gone through a selection of organic academic groups worldwide who have interest in olefin metathesis, organic metals, polyacetylenes, and organic supercons Most politely declined up front. I've got a very small number who opened a dialog. I only need one good one.

Polarizability is the key, as stiffness and redox potential (lambda max), perhaps also state conversion as in fluorescence. Benzil to 2,3-diphenylbutadiene then olefin metathesis polymerization (extrude ethylene) is a cheap first effort for shakedown. One can get fancy by bezoin condensation of 4-nitro- and 4-dimethlaminobenzaldehyde. That eventually gives an alternating push-pull polyacetylene. Reduce the nitro group in the diene monomer to aniline. Now you can methylate to get the exceedingly electron-rich very soft homopolymer poly(4-dimethylaminophenylacetylene). Or diazotize the aniline and make a whole warehouse of azo dye or condensed ring fluorescent chromophore monomers.

Its a great way to spin wheels. Substituted polyacetylenes are interesting as chemosensors. Will any of them be high temp supercons?

We'll see where this goes.


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Quote:
Originally posted by Uncle Al:

Nobody has a Dry Ice supercon much less a room temp one. The commercial potential is awesome. Consider medical MRI with mechanical refrigeration isenad of liquid helium. That alone will make you rich.

Theory can predict anything - directly or by sneaking up as perturbation series or Yukawa potentials. Anything reasonable must be reduced to practice to truly know.

I have an above room temperature superconducting phase that consists of entangled electrons. A current cannot flow through it, but electrons can be teleported across it (an EPR effect). Furthermore, I have the mechanism for superconduction when a current flows through a material (no perturbation analysis required only a simple quadratic equation); and it is predictive. The Cooper mechanism does not manifest: this has dire consequences for quantum field theories. Paper has been submitted.

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The Einstein-Podolsky-Rosen paradox cannot superluminally transmit information. If you are quantum teleporting an electric current va EPR then you could in principle superluminally send Morse code.

You've got problems.


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Quote:
Originally posted by Uncle Al:
The Einstein-Podolsky-Rosen paradox cannot superluminally transmit information. If you are quantum teleporting an electric current va EPR then you could in principle superluminally send Morse code.

You've got problems.
It is basically the same principle, once one realises that quantum mechanics must be visualised in terms of wave entities and not in terms of "particles" which are "uncertain". Schroedinger did solve the problem but allowed Bohr, Born and Heisenberg to intimdate him. Two entangled "particles" are in instant contact with each other because they form a single wave-entity within which time does not manifest. This also happens when a covalent bond forms, or a photon entangles with an electron orbital around an atom to in this way get it to morph into a new holistic electron wave entity with a higher energy. This also happens when a photon entangles with an electron within a metal to eject a photo-electron etc. There is no "classical" colision involved. Thus if you make a measurement that disentangles two entities, they do it in a correlated manner even when light years apart. After they have disentangled, they cannot communicate with each other faster than light speed anymore.

The superconducting phase forms between positive charges below the diamond's surface and positive charges on the anode; i.e. it is in effect a "macro chemical bond". The electrons first form bi-electron Gaussian shaped waves which then entangle to form the equivalent of a laser beam; however, in the case of the electrons the beam forms as a perfect stationary black cylinder between the diamond and the anode. It is a "single entity" within which time does not manifest, so there are no charge-carriers that can move through it. The electrons injected at the diamond "teleports" from the diamond to the anode and also vice versa. You can teleport such a large current that any other material would melt or glow white hot if such a current flowed through it. The superconducting cylinder stays black even when the anode starts to melt.

Thus if it were possible to form such an entangled electron beam between the earth and Mars, near instantaneous communication will be possible. You will then be able to send Morse code superluminally; however, why use Morse code instead of a telephone?

It might sound like science fiction but what I am saying here is based on experimental facts. Goodbye Copenhagen interpretation!!

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Quote:
Thus if it were possible to form such an entangled electron beam between the earth and Mars, near instantaneous communication will be possible. You will then be able to send Morse code superluminally...
Uncle Al stands corrected. You don't have a problem. You have an insurmountable error. You are wrong. Physical reality is causal.

Little's proposal is wholly consistent with physics. Whether obtained polymers are (high temp) supercons or not merely requires observation of examples. Nothing you have posted could possibly be true.

BTW, diamond is not a blackbody emitter. 1000 C diamond does not glow: It is still well below its Debye temperature (at least 1500 C).


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Quote:
Originally posted by Uncle Al:
Quote:
Thus if it were possible to form such an entangled electron beam between the earth and Mars, near instantaneous communication will be possible. You will then be able to send Morse code superluminally...
Uncle Al stands corrected. You don't have a problem. You have an insurmountable error. You are wrong. Physical reality is causal.
He is not precisely incorrect. He has the magic word "if" in there. If A then B. Since known physics states that B is not possible, then A must be false. I.e. one can not set up an entangled electron beam between earth and Mars.

As to the original subject, let's see if I have this correct:

1) The chemistry is cheap
2) the chemistry is straitforward
3) Uncle Al is a chemist
4) The rewards are incredible fame and glory

The next step--asking someone else to take over the project doesn't exactly follow to me. The outcomes I see, in order of decreasing probability are:

1) no one does the project
2) someone does the project and it doesn't work
3) someone does the project, it works and Uncle Al is mentioned in the aknowledgements.

The future is made. Why are you content to stand back and let others create it?

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Quote:
Originally posted by Uncle Al:
Quote:
Uncle Al stands corrected. You don't have a problem. You have an insurmountable error. You are wrong. Physical reality is causal.

Little's proposal is wholly consistent with physics. Whether obtained polymers are (high temp) supercons or not merely requires observation of examples. Nothing you have posted could possibly be true.

BTW, diamond is not a blackbody emitter. 1000 C diamond does not glow: It is still well below its Debye temperature (at least 1500 C).
The phase is NOT diamond. So it has nothing to do with diamond's black body properties at all. By the way diamond's Debye temperature is about 1800 C. What you see between the diamond's surface and the anode is a black cylinder of length up to 20 microns and even 135 microns) with a diameter of about 1 micron. It consists totally of entangled bi-electron waves. If you open the gap by too much and break tht phase, the residue gets sucked back slowly into the anode and/or the diamond.

To generate such a phase between Earth and Mars is probably impossible; but to generate it on a processor chip so that you have superluminal signal transfer without heat generation is possible.

If nothing I have posted could possibly be true, are you willing to bet your reputation on it and come clean when it is proved to be correct within the next two years? How much of your reputation are you willing to put on the line? All?

I agree with you on one point and that is that Physical Reality is causal; however, by sending a superluminal signal through a matter-phase does not violate causality. It only happens when you send such a signal through space. An entangled matter-wave occupies space and is stationary relative to its proper inertial reference frame; it is not space-time itself.

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To "J. Arthur God" You've never done olefin metathesis on hindered substrates. Grubb's cataylsts are commercially available but Schrock's - especially adept at working hindered and unstrained substrates - are not.

You do not do organic synthesis or you would know the Wittig reaction is intolerant of hindered carbonyls. Benzil systems will not do well in alkaline reducing conditions.

"Collaboration" Academic groups particularly skilled in executing the polymerization and studying the results do not contain the skills to obtain required monomers.

Naval shells are interesting when they land, but they lack a cute little button on their buttoms to send them on their way.


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Quote:
Originally posted by Uncle Al:
To "J. Arthur God" You've never done olefin metathesis on hindered substrates. Grubb's cataylsts are commercially available but Schrock's - especially adept at working hindered and unstrained substrates - are not.

You do not do organic synthesis or you would know the Wittig reaction is intolerant of hindered carbonyls. Benzil systems will not do well in alkaline reducing conditions.

"Collaboration" Academic groups particularly skilled in executing the polymerization and studying the results do not contain the skills to obtain required monomers.
So, it isn't an easy thing to do?

Perhaps you need to be more precise in your language. From your website, I read:

"If Little had theoretical basis for his proposal sufficient to pass peer review, it should be honored by doing the now facile experiment. "

Dictionary.com defines "Facile" as
"Done or achieved with little effort or difficulty; easy."

Don't stress it, many people, including myself, often use the English language in a sloppy manner.

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A very interesting discussion you Boffins are having, as well as entertaining.
I dont profess to understand much more than 10% of the above.

But I would like to take this opportunity of asking Johnny Boy (Cathodix) a question about Diamonds.

I am aware of their High refraction index, high thermal conductivity. And that doped diamond semi-conductors, could be made more radiation resistant due to their higher ionization property.
etc
Question- Do Diamonds exhibit a Negative electron affinity in a vacuum? ie. do their surfaces spontaneously emit Electrons in a vacuum?
If the above is true, then a diamond or diamond film, wired as a (cold) cathode, combined with a high positive grid/anode, could be the subject of some very useful detecting/experiments?

Any comments would be very useful.


.

.
"You will never find a real Human being - Even in a mirror." ....Mike Kremer.


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Quote:
Originally posted by Mike Kremer:

But I would like to take this opportunity of asking Johnny Boy (Cathodix) a question about Diamonds.

Question- Do Diamonds exhibit a Negative electron affinity in a vacuum? ie. do their surfaces spontaneously emit Electrons in a vacuum?
If the above is true, then a diamond or diamond film, wired as a (cold) cathode, combined with a high positive grid/anode, could be the subject of some very useful detecting/experiments?

Any comments would be very useful.
My experiments show that diamond does indeed have negative electron affinity (NEA); however, the idea that you can then extract AND ACCELERATE electrons by just using any anodic voltage is wrong. If this happens you violate the second law of thermodynamics. The reason for this is that at any electronic interface, charge carriers are exchanged in order to establish thermodynamic equilibrium. This also happens at an NEA interface to the vacuum.

When generating a surface to an NEA n-type material, the electrons in the conduction band find themselves at a higher energy than the vacuum level and they DO then emit spontaneously into the vacuum; however, by doing this they leave a positively charged depletion layer under the surface which attracts them back so that an equilibrium dipole layer is formed consisting of the ejected electrons and the depletion layer. When you now apply a field to the surface, further electrons are ejected; HOWEVER, they are not accelerated to the anode; they just add to the external electrons to make the dipole wider. Only when width of the external electron-layer has increased by so much that it touches the anode, can a current start to flow.

This current can still not act as a cold cathode current because of the following: When increasing the field further, you are also increasing it over the depletion layer: so more electrons are added to the gap. This increase in carrier density causes a decrease in the electric field between the diamond and the anode and over the depletion layer. An equilibrium current, as demanded by the second law of thermodynamics, is only established when this field becomes zero. An equilibrium current then flows because there is no field between the diamond surface and the anode. When a current flows between two contacts without an electric field being present you have superconduction. In fact this experiment is the first experiment ever that unequivocally proves that a current can flow between two contacts without an electric field being present AND THIS OCCURS AT AND ABOVE ROOM TEMPERATURE. Not even the manifestaion of the Meissner-effect proves that THERE IS NO ELECTRIC FIELD INVOLVED.

Thus to have real cold cathode action, one must prevent the superconducting phase from forming. Knowing the mechanism this is possible, and I have filed a patent on how to manufature cold cathodes and demonstrated experimentally that this is possible.

I hope this is of help.

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Johnny Boy,

I checked out your webpage. I have to ask about a statement in the "patents" section.

"The patent covers all materials that superconduct above 200?K."

This isn't a dig, but how do you get around the subject of obviousness? Enough has been written about applications of room temperature superconductors that I would think it impossible to get a defensible patent on this.

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Quote:
Originally posted by J. Arthur God:
Johnny Boy,

I checked out your webpage. I have to ask about a statement in the "patents" section.

"The patent covers all materials that superconduct above 200?K."

This isn't a dig, but how do you get around the subject of obviousness? Enough has been written about applications of room temperature superconductors that I would think it impossible to get a defensible patent on this.
Good question! The reason is that I have found the actual mechanism that is responsible for all types of materials and phases that superconducts by means of a current flowing through them. It is NOT BCS!! In fact BCS cannot explain superconduction and neither can it predict how one should modify a material to make it superconducting. Knowing the mechanism you can calculate the parameters that have to apply when you want to have a superconductor that must have a chosen critical temperature. One cannot claim these parameters for superconductors that have already been discovred by trial and error, because these materials already have the correct parameters. Thus we claim the paramaters that have to be optimised and the values that have to apply for superconductors that have not yet been reported in the literature: i.e. all those above 200 K. The patent claims a method to test whether a material is suitable for superconduction and how to then modify the material in order to get it to superconduct above a chosen critical temperature.

The patent also claims methods to generate superconductors that consist of entangled electrons through which other electrons can be teleported.

A short summary of the mechanism is given on my webpage. I have also written a paper and submitted it. Pasti urged me to follow the latter route, which I at first opposed. Nonetheless I started the manuscript reluctantly, and am now glad that I did write it. The paper worked out very well indeed.

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What you describe doesn't sound to be to be exactly the same thing as patenting all materials that superconduct above 200K.

First, keep in mind that (in in the US at least) you can not patent physics. Physical structures and methods to produce, yes, but not the underlying physics. In my experience, claiming the parameters that have to be optimized sounds like a tough sell to the USPTO. Actually, it would be a tough sell to our patent attorney. In case of a challenge to the patent, it is a really tough sell.

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Quote:
Originally posted by J. Arthur God:
What you describe doesn't sound to be to be exactly the same thing as patenting all materials that superconduct above 200K.

First, keep in mind that (in in the US at least) you can not patent physics. Physical structures and methods to produce, yes, but not the underlying physics. In my experience, claiming the parameters that have to be optimized sounds like a tough sell to the USPTO. Actually, it would be a tough sell to our patent attorney. In case of a challenge to the patent, it is a really tough sell.
AS a physicist I do not really understand legalese; however, my patent attorneys are very astute and have acted for some of the largest international corporations.You have put it better: What is patented are "physical structures and methods to produce". I know that big firms with money do not mind stealing ideas and then allow endless law proceedings to kill off the actual inventor who deserves to be rewarded. Everybody knows that once the mechanism is known for superconduction so that predictions can be made and such materials designed and developed, it will be akin to finding the holy grail. One would think that under these circumtances the law and human decency will allow the actual mechanism to be patented. But it only shows again what society thinks of scientists: "they must be on tap NOT on top". Their intellectual work is there for "stealing" not "rewarding". I realise all too well that one needs a strong BIG BROTHER to protect you.

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