“Biologist realizes he’s been studying Cadbury egg”: Mislabeled bottle leads to Phys Rev B retraction

The quote in the title of this post is a potential Onion headline that didn’t make it into print. It was part of an episode of This American Life that aired last week, and it seemed apropos, even though the subject here is superconductors rather than biology.

After all, we’ve written about a retraction that resulted from ordering the wrong mice. Today, we bring you the tale of a retraction caused by a mislabeled bottle. According to a retraction notice that appeared online last month in Physical Review B:

Recently we published a paper entitled “Superconductivity in the Rh-based Heusler familyMRh2Sn” [Phys. Rev. B 82, 134520 (2010)]. Due to the mislabeling of a rebottled chemical-starting material, the superconductors originally reported in this paper as Rh intermetallics are now known to be Pd intermetallics. The basic superconducting properties of the Pd compounds have been previously reported.

We are sorry for this error, and ask that the paper not be regarded as part of the scientific literature. The retracted manuscript includes some previously unpublished data on Pd Heusler superconductors, which with suitable reanalysis may be appropriate for reporting in a different publication.

Rh, for those of us who haven’t memorized the periodic table of the elements, is rhodium. Pd is palladium.

We asked senior author Robert Cava of Princeton how he learned about the error, and what’s likely to happen next:

After the paper was published we came in contact with another research group that was working on similar materials. They told us informally that their results did not agree with ours. We tried to figure out why, and found out that a scientist who was not involved in our project had rebottled an elemental metal and accidentally mislabeled the bottle. The elemental metal in the mislabeled bottle was used by our group as one of the starting materials for our synthesis. Therefore the compounds we reported on in the publication had the incorrect chemical formulas.

This has never happened to me previously in my thirty years of research.  When we discovered this error we immediately contacted the editors of Phys Rev B to retract the paper. We are currently working to properly synthesize our original target compounds and report their properties.

Kudos to Cava’s team. We wouldn’t label this as anything but transparent science at its finest.

Hat tip: Adam Johan Bergren.

5 thoughts on ““Biologist realizes he’s been studying Cadbury egg”: Mislabeled bottle leads to Phys Rev B retraction”

  1. I agree that it’s transparent science at its finest. They screwed up, they found out because of good scientific protocol, they notified those who needed to know. Well done.

    So perhaps you shouldn’t have succumbed to the cheap pleasure of snarkiness with that headline, which drips of ridicule rather than praise. “Transparent science at its finest” would have fit nicely.

    After all, it’s not like this site has a shortage of excuses to make fun of people.

    1. Dave — I see where the headline could be read that way. It first hit me a different way, as something cute that the scientists themselves might use in later years, in telling a Fiorello LaGuardia kind of “When I make a mistake it’s a beaut!” kind of story.

  2. Cavas is also an Editorial Member of Phys Rev B (http://prb.aps.org/staff). It was brave and honest of him to come out with the mistake, but you also have to realize that the stakes for him were even higher given his position within the journal that published the original article. Yes, it is an embarrassment now, but it would have been a potential catastrophe for him down the road had he not revealed the error. I think, once the discrepancy was pointed out by that other group, the retraction was his best option.

  3. While I laud the transparency, the group who synthesized and measured the material is not without fault. As someone who has grown superconducting samples, the first tests you preform are to determine that you grew the material you were attempting to grow. It should be apparent in any XRD or EDS scan that Pd is present and not Rh. That being said, it’s a case of extreme negligence rather than wrongdoing.

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