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Robert Palgrave

@robertpalgrave.bsky.social
771 followers 185 following 54 posts

Professor of Inorganic and Materials Chemistry at UCL. Director of UK National XPS Service.

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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
...but them being hard to make means they will have to be even better at their job to make manufacture worthwhile. A difficult conundrum to solve. To me computation seems much better as a focused tool for understanding a material of interest, rather than a discovery method.
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
Fact is shovelling stuff into a furnace is pretty easy. And diffraction is pretty easy. That accounts for so many oxides and metal alloys being known. Typing to beat the furnace in discovering those - I'd say good luck. Success will come from niche compounds that are hard to make
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
As far as I know, none of those kinds of materials can be discovered with current ab initio methods. But even the material types that are idealised for computation - crystalline, simple composition, no disorder... are there examples of these discoveries led by computation? I'd say not many.
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
I'd also note the original table was about materials discovery specifically, not calculation in general. Materials can be non crystalline, or composite, or nanoscale, or have texture, impurities, or compositional disorder. In fact most useful materials fall into at least one of those.
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
to a high degree without computational theory (meaning an ab initio) Examples are all the proteins and enzymes Hodgkin solved, all the structures Braggs solved, all the organic molecules that were essentially solved before even diffraction (Kekule - even if some had to rely on dreams)
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
The table is tongue in cheek for sure... and of course we need both experiment and computational theory. I would also say although there can be no observation without theory (theory in the most general sense) - in materials science it is quite possible to work out 'what this stuff is'...
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Robert Palgrave @robertpalgrave.bsky.social · 01/05/2025
Pocket guide to materials discovery calculation methods (repost from the other place)
A table comparing the computational power of HPC and a furnace
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Robert Palgrave @robertpalgrave.bsky.social · 16/04/2025
Add to cv anyway
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British Crystallographic Association @crystallography.org.uk · 15/04/2025
@robertpalgrave.bsky.social delivers the PCG plenary lecture at #BCA25 "The role of AI in materials discovery"
Robert Palgrave lecturing on the role of AI in materials discovery
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Robert Palgrave @robertpalgrave.bsky.social · 07/03/2025
This is why everyone falls in love with solid state chemistry - first year lab straight out of Harry Potter
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Robert Palgrave @robertpalgrave.bsky.social · 23/01/2025
Nice visit to the European Commission to discuss AI in materials!
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Robert Palgrave @robertpalgrave.bsky.social · 13/01/2025
The UK National XPS Service now on bluesky!
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Robert Palgrave @robertpalgrave.bsky.social · 09/01/2025
You can select the style, it can be anything! Gospel, prog rock, nasheed... In any language too...you just enter the lyrics and describe the style. The website isn't specifically for academic papers, but maybe we can create a new genre!
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Robert Palgrave @robertpalgrave.bsky.social · 09/01/2025
Original paper here papers.ssrn.com/sol3/papers....
papers.ssrn.com
When is a Lattice Not a Lattice? The changing meaning of the term lattice in crystallography and physics
The concept of the lattice is central to the understanding of crystalline solids. However, usage of this word can very often differ between crystallographers, f
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Robert Palgrave @robertpalgrave.bsky.social · 09/01/2025
Hey it's 2025 so here's a version of our Lattice paper as a AI generated trance track suno.com/song/a512663...
suno.com
Lattice by @xpsbeats | Suno
[Spoken, Synthwave, Trance, Heavy Trap Drums, Dubstep Breaks, Neon Vocals, Retro Futuristic, trance] song. Listen and make your own with Suno.
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Safia | صفية @finetraces786.bsky.social · 31/12/2024
I feel like it is important to share that once @cesapo.bsky.social and I asked Fraser Stoddart what his favorite swearword was, and his wholesome voice he said, “nincompoop.” 🥲 #Chemsky
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Robert Palgrave @robertpalgrave.bsky.social · 29/12/2024
Yes very much agree, but I think electroboom had the better video on this one topic
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Robert Palgrave @robertpalgrave.bsky.social · 29/12/2024
Also see the rebuttal from the incomparable electroboom youtu.be/iph500cPK28?...
youtu.be
How Wrong Is VERITASIUM? A Lamp and Power Line Story
YouTube video by ElectroBOOM
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Robert Palgrave @robertpalgrave.bsky.social · 29/12/2024
Interesting video on this youtu.be/bHIhgxav9LY?...
youtu.be
The Big Misconception About Electricity
YouTube video by Veritasium
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Robert Palgrave @robertpalgrave.bsky.social · 29/12/2024
Facts are invented not discovered
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Robert Palgrave @robertpalgrave.bsky.social · 29/12/2024
Twitter is getting really really weird x.com/jlippincott_...
x.com
x.com
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Robert Palgrave @robertpalgrave.bsky.social · 28/12/2024
It's always been clear most out-and-out racists voted Tory. I'd always wondered what would happen if their votes were subtracted. Last GE we found out. If left is reasonably united Tories can't win without the Reform vote. That's why they are scrabbling to the right.
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
I do appreciate all your replies and definitely not tl;dr! Happy Christmas!
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
These are the people I'm replying to. Their mental model is that all the IR is absorbed as pure CO2 does in a short tube because if its high attenuation. It *is* a superficially convicting argument. By showing that some IR is escaping earth that proves that model is wrong.
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
Thanks for all these helpful posts. I do think this that when laymen deniers use 'saturated' they mean it in a different sense. They mean all the IR is absorbed by CO2 and none is left to absorb, based on simple ideas about absorption coefficients. E.g. these replies on twitter
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
I understand that CO2 emits as well as absorbs, and that the 650cm-1 light escaping earth has been absorbed and emitted many times My point was to address the specific wrong claim very often used by deniers with as direct an observation as possible, which they'll find hard to dismiss
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
I thought the best observation to disprove this is to show that in fact 650cm-1 light is radiated from earth, showing that the atmosphere isn't saturated in the way described in those papers
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Robert Palgrave @robertpalgrave.bsky.social · 25/12/2024
What 'they' mean by saturated is that 1 atm air absorbs 650 cm-1 to 99.99....% over a small distance compared with the thickness of that atmosphere. They conclude that none of the IR from ground reaches space, so adding more CO2 has no effect.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
The saturation theory is tested and falsified by these observations. Even though it seemed intuitively right, it is in fact wrong. That's what makes it the ideal tool to keep pushing climate change denial.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Another balloon flight from 2005, this time to 27km Again CO2 not saturated.
Mlynczak et al. GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L07704, doi:10.1029/2005GL025114, 2006
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Here is a spectrum of Earth taken from the Mars Global surveyor in 1996. Again the emission in the CO2 band is not zero meaning the atmosphere is not saturated, and 15 micron light is escaping.
Christensen and Pearl, JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 102, NO. E5, PAGES 10,875-10,880, MAY 25, 1997
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Here is the spectrum of earth taken by Nimbus satellite in 1970. Note the dip at 650 cm-1 due to CO2 absorption, but this dip doesn't go to zero, meaning some 15 micron light escapes.
Hansel, Rudolf A., et al. (1994), IRIS/Nimbus-4 Level 1 Radiance Data V001, Greenbelt, MD, USA, Goddard Earth Sciences Data and Information Services Center (GES DISC)
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
That measurement has been done by balloons satellites and spacecraft since the 1960s. Here is the spectrum taken at 31km by balloon in 1966. The CO2 absorption at 650 cm-1 is clearly present. But radiance at 650 cm-1 is not zero. So the atmosphere is not saturated at 31 km.
W. Bandeen, Experimental approaches to remote atmospheric probing in the infrared from satellites, https://ntrs.nasa.gov/citations/19720017727
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
And there is a very simple experiment that can be done to test this. If the atmosphere is indeed saturated, then CO2 should be absorbing all of the 15 micron radiation. What if we measure the emitted IR light from the Earth? Saturation theory says this should be zero.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
So if the partial pressure of CO2 falls, that means the IR absorption of CO2 falls with altitude. Eventually, even if saturated at ground level, the atmosphere won't be saturated at some height. Adding more CO2 will meaningfully increase the IR absorbed at that height
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
The atmosphere gets thinner as you go up. That means the partial pressure of CO2 decreases with altitude, even though the ppm of CO2 stays the same - because the total pressure is falling.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Analogies like "adding more blankets doesn't make you warmer", "quadruple glazing doesn't keep you warmer than triple glazing" etc seem to back this up. The analogies are intuitive but miss a crucial feature of the atmosphere:
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Some of the papers posted by Lord Young even do experiments where they measure the absorption of 15 micron light by different ppms of CO2 and see barely any difference.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
The idea of saturation is that the atmosphere already has enough CO2 in it to absorb all of the 15 micron (IR) radiation that comes from the earth's surface. By that argument, adding more CO2 won't absorb more IR because it is already all absorbed.
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Robert Palgrave @robertpalgrave.bsky.social · 24/12/2024
Lord Toby Young has posted a rehashing of the "CO2 is saturated" meme. It sounds plausible, and some eminent scientists believed it back in history. But we've known for 100 years that the atmosphere isn't saturated with CO2 And one very simple observation shows it beyond doubt.
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Sean | Drowned in Sound @drownedinsound.bsky.social · 24/12/2024
😬😬😬
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Robert Palgrave @robertpalgrave.bsky.social · 17/12/2024
Another amazing SSCG Christmas Meeting at the University of Birmingham comes to an end, a fascinating range of talks as usual and great to catch up with many friends. Congrats to the organisers! Can't wait for next year!
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Martijn Zwijnenburg @zwijcompchem.bsky.social · 17/12/2024
Rob Palgrave (@robertpalgrave.bsky.social) from UCL kicking off the morning after the night before of #SSCGXmas with a talk on the (structural) chemistry of halide perovskites #chemsky
Ghosts of SSCGXmas meetings pastPerovskite tolerance factorsSay something here about AI
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Robert Palgrave @robertpalgrave.bsky.social · 16/12/2024
How you know Christmas has really begun: start of the RSC Solid State Chemistry Christmas Meeting at University of Birmingham
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Dr. Christine Beavers @xtalgrrl.bsky.social · 12/12/2024
So, as a new member of the US National Committee for Crystallography, I've been tasked with looking into workforce development. So I'd like to ask you #chemsky peeps how you learned about crystallography? Reply and retweet, I wanna hear from as many of you as possible!
media.tenor.com
a large diamond is surrounded by blue water on a black background .
Alt: a large diamond is surrounded by blue water on a black background .
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Robert Palgrave @robertpalgrave.bsky.social · 10/12/2024
Yeah I will do! Frustrating as the reviewer is clearly an XPS expert who knows about all the bad XPS that gets published, but still insists methods papers are just hidden is specialist journals
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Robert Palgrave @robertpalgrave.bsky.social · 10/12/2024
still a mystery why bad XPS is all over the literature.
media.tenor.com
Suspect Guilty GIF
ALT: Suspect Guilty GIF
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Robert Palgrave @robertpalgrave.bsky.social · 10/12/2024
I never normally do this - but got this review today on a paper about XPS fitting of some very topical compounds that literally every paper in the field gets wrong
Reviewer 2: "I do agree that many papers can be found with bad XPS fits, this is not specific to [this material] but a problem for the field as a whole.... There are estimates that more than half of the published XPS data has significant faults (DOI: 10.1063/5.0086359 . But this is not a topic suitable to [moderate JIF journal in materials chemistry].”
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Robert Palgrave @robertpalgrave.bsky.social · 10/12/2024
Congrats Mario! Look forward to reading it
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Aisha Mumtaz @aishamumtaz.bsky.social · 09/12/2024
Next up... XPS themed biscuits for my visit to Harwell 🤓🍪🧪 #Chemsky
Giant biscuit in the centre shaped as an XPS spectrometer. Square shaped biscuits designed as the harwellxps logo and small circle shaped biscuits designed as electrons around it. The biscuits are brown decorated with blue, green, white and black icing.Two square shaped biscuits with the harwell xps logo. Both are blue and green in the background. The left one has the logo design in black while the right one has it in white
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