Microscopic Insights into the Anomalous Heat Effect that Unify Disparate Experimental Results
Graham K. Hubler
Abstract and summary · read the original at the source
In one page
Graham Hubler, a materials physicist at the University of Missouri, asks why the anomalous heat effect — the excess heat reported from hydrogen-loaded palladium and nickel since 1989 — turns up in so many different set-ups and so unpredictably. His answer rests on a single assumption: the effect needs one particular optical phonon resonance, a specific frequency of neighbouring atoms vibrating against each other in the lattice, coupled to electromagnetic radiation of the same frequency. Hit that resonance and heat follows; miss it and nothing happens. He builds the case from three ordinary materials measurements — a nuclear-probe strain measurement he made at CERN, a 61 kelvin superconducting phase found in quenched palladium deuteride, and forty-year-old internal friction data — and reads a recipe off them: get about thirty percent of the deuterium into the smaller tetrahedral sites or make plenty of vacancies, keep loading below about 0.64, work with sub-ten-nanometre particles, texture the metal. He closes with the experiments that would confirm or kill it.
Why it matters hereChapter 12 holds that a loaded metal lattice does nuclear-scale work at ordinary temperatures, and the standing question there has always been reproducibility. Hubler converts that question into a materials specification — which interstitial sites the deuterium occupies, which phonon frequency, which particle size, which crystal texture — which is exactly the form chapter 1’s evidence ladder can act on: a stated mechanism with named experiments attached.
What it claims
01The anomalous heat effect requires a specific-frequency optical phonon resonance that couples to electromagnetic radiation of the same frequency; once triggered, the effect itself produces either the right phonon or the right radiation and so feeds back to sustain the resonance, because a phonon resonance is oscillating charge and radiates at its own frequency.Abstract; Section 1; Section 3, the sustaining-feedback paragraph
What to watch02In a perturbed angular correlation experiment at the ISOLDE facility at CERN, radioactive hafnium implanted into palladium foils reported the local strain around the probe nucleus during electrochemical loading: above about 0.5 loading the strain is 43 percent larger for deuterium than for hydrogen, which Hubler reads as roughly thirty percent occupation of the smaller tetrahedral sites by deuterium in the dynamic surface region.Section 2, Figure 1 and the closing paragraph of the section
Published and peer-reviewed03Syed and colleagues soaked palladium in 100 bar deuterium at 300 degrees Celsius and quenched it, finding a superconducting transition at 61 kelvin where palladium deuteride has been known for fifty years to transition at 11 kelvin — with about thirty percent tetrahedral site occupancy frozen in, no crystal phase change, and the phase stable up to room temperature.Section 2, Figure 2
Published and peer-reviewed04Internal friction data for palladium hydride show the hydrogen-diffusion loss peak maximising near 0.64 loading and then falling away as adjacent sites fill and diffusive jumps are blocked, and dislocations locking above about 0.55 — so if diffusion dynamics are what populate the tetrahedral site, the effect should favour loadings below about 0.64, consistent with Storms’ long-standing report of heat at loadings as low as 0.3.Section 2, Figure 3
Published and peer-reviewed05The recipe that follows: in bulk palladium, either significant deuterium in tetrahedral sites or a high vacancy concentration, with sub-ten-nanometre palladium particles deposited on the surface and the metal textured along the 100 direction; in nickel, nanostructure below about fourteen nanometres, where the running temperature is above the Debye temperature and heat alone is the trigger, which is why nickel systems are more reproducible than palladium in electrolyte.Section 3, the summary rules; Section 4
Designed, not yet built06Hubler’s reading is that the anomalous heat effect is first a solid-state physics problem rather than a nuclear one — its only signatures are heat, radio-frequency emission and no energetic nuclear emissions — and he names the measurements that would open it: internal friction with deuterium rather than hydrogen, the 61 kelvin palladium deuteride run in a heat apparatus with triggering, characterised radio-frequency emissions, Mössbauer spectroscopy on cobalt-57 during heat events, and vacancies introduced by a reactor neutron flux.Section 5, the lessons list and the suggestions for future fundamental experiments
What to watch
Read it · abstract
Abstract
The anomalous heat effect (AHE) has many embodiments including hydrogen loading by electrolysis, high and low hydrogen pressure over elevated temperature nanostructures, ultrasound, and glow discharge loading. The AHE was triggered by variable charging current, temperature fluctuations, high voltage pulses, laser pulses, ultrasound, and electrolysis time. Pd materials for which the AHE has been reported include wires, cylinders, foils, and nanoparticles. Ni materials for which the AHE has been reported include constantan wires, Ni in zeolites, and Ni nanostructures. It is highly likely that the same AHE mechanism underlies all these embodiments despite their seemingly wide differences. Many investigators involved in research on the anomalous heat effect (AHE), including this author, are of the opinion that phonons in Pd and Ni play a role in generating and sustaining the AHE. Here it is hypothesized that the AHE requires a specific frequency optical phonon resonance that couples to electromagnetic radiation of the same frequency. If it can be arranged to sustain this specific, resonance, then the AHE is produced. It is demonstrated how this one assumption, coupled to several recent experimental results, can lead to useful microscopic insights that unify disparate experimental results under one umbrella and that may also be useful to guide further experiments.
The way in
https://doi.org/10.70923/001c.124941Published as J. Condensed Matter Nucl. Sci. 38 (2023) 78–88, from The Medical School, University of Missouri, Columbia. The article carries ’© 2023 ICCF. All rights reserved. ISSN 2227-3123’ and no Creative Commons statement, so this page carries the summary, the claims and the author’s own abstract and sends the reader to the source. The full text is free to read at the journal, jcmns.org/article/124941.pdf.
How to cite it
Graham K. Hubler (2024) Microscopic Insights into the Anomalous Heat Effect that Unify Disparate Experimental Results. doi:10.70923/001c.124941
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