Electro-Optics Paper Retracted | March 10, 2014 Issue - Vol. 92 Issue 10 | Chemical & Engineering News
Volume 92 Issue 10 | p. 34
Issue Date: March 10, 2014

Electro-Optics Paper Retracted

Materials science paper fails to cite inventor of chromophores used in research
Department: Science & Technology
News Channels: Materials SCENE
Keywords: retraction, chromophores, Larry Dalton

A 2004 paper in the Elsevier journal Inorganica Chimica Acta has been retracted for failing to acknowledge the contributions of another scientist’s work included in the article (Inorg. Chim. Acta 2014, DOI: 10.1016/j.ica.2014.01.004).

The paper, “Advances in Organic Electro-Optic Materials and Processing,” was authored by University of Washington chemistry professor Larry R. Dalton and several members of his group. Dalton at the time headed the University of Washington’s multi-million-dollar Center on Materials & Devices for Information Technology Research (CMDITR). The paper described a new method for measuring molecular hyperpolarizability, an electronic property that is crucial in the development of materials that convert electrical signals into optical ones. Industry is eyeing such materials for ultrafast computers and communications devices.

To demonstrate the method, Dalton’s team used a class of electron donor-acceptor dyes called tricyanopyrroline (TCP) chromophores. But in their paper they failed to disclose that those chromophores were invented in the early 2000s by Bart Kahr, at the time a chemistry professor at the University of Washington, and his former postdoc Sei-Hum Jang.

After synthesizing the chromophores, Jang began preparing a paper, and he and Kahr filed for a patent.

Meanwhile, Jang had also begun working with chemistry professor Alex K-Y. Jen, who was part of Dalton’s center. Jang prepared the chromophores for the hyperpolarizability experiments in Kahr’s lab. Both Jang and Kahr were then surprised to discover that that work had been published by Dalton and his colleagues (Inorg. Chim. Acta 2004, DOI: 10.1016/j.ica.2004.07.031). Neither Jang nor Kahr had been told about the publication, and although Jang was listed as an author, Kahr was not. Jen was thanked in the acknowledgments section of the paper for his assistance.

The ICA retraction directs scientists to a subsequent paper, “Pyrroline Chromophores for Electro-Optics,” “for a complete account of research related to the TCP chromophores.” That paper was published in the American Chemical Society journal Chemistry of Materials in 2006, and it did include Kahr as an author and inventor of the TCP chromophores (Chem. Mat. 2006, DOI: 10.1021/cm052861i).

Elsevier did not respond to C&EN’s request for comment.

Dalton tells C&EN that the omission was the result of a number of communication failures. One failure was that he had given responsibility for the paper to two graduate students, one of whom didn’t realize the history of the chromophore’s development.

Jang brought the omission to CMDITR’s attention back in 2005, but he was rebuffed. Kahr continued working with the group but became increasingly concerned about other, more fundamental issues with the center, some of which were detailed in a 2012 news story in Nature (DOI: 10.1038/489017a).

Most important, Kahr says, the center failed to report to the National Science Foundation in grant applications that a key property of the center’s star materials was under question. Indeed, experiments by Kahr showed that the materials’ ability to line up in an electrical field, to which their remarkable electric-to-optic signal conversion abilities were attributed, was very weak.

Kahr moved to New York University in 2008. He then asked for an investigation into these issues, including the now-retracted ICA paper, by the University of Washington’s Office of Scholarly Integrity. The office found no evidence of wrongdoing and decided that the question of the 2004 paper’s authorship was the purview of ICA.

However, a Feb. 25 post on the blog Retraction Watch noted that in 1967, Dalton retracted a paper from the very same journal, ICA, after quoting results from a Russian team without ­acknowledgment.

Regarding the 2004 paper, according to Kahr and Dalton, it took much wrangling with the journal before the three parties reached a decision.

“The paper violated the journal authorship guidelines and was retracted, as it should be,” Kahr says.

“The last thing I wanted to do was claim credit for the material,” Dalton says. “The only resolution we could work out was to retract the article and refer to the 2006 publication, because no one will dispute that.”

Chemical & Engineering News
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Copyright © American Chemical Society
Mark Hollingsworth (March 5, 2014 8:06 PM)
Although the University of Washington’s Office of Scholarly Integrity found that authorship of the 2004 paper was within the purview of ICA, the dean of the College of Arts and Sciences (now university provost) Ana Marie Cauce took up the issue and in July 2011 wrote the following to Kahr:

"Because of your concern, however, we asked Dr. Dalton to consider whether you should be a co-author. He concluded that your role in connection with the paper was in contributing to the production of the TCP chromophores, but otherwise that your contribution did not rise to the level where it would be appropriate to list you as a coauthor. He did conclude, however, that your role warranted acknowledgement, and, accordingly, last December he sent to the editors of Inorganica Chimica Acta a letter (copy enclosed) requesting publication of an erratum acknowledging that you contributed to the production of the materials.

In summary, we found no evidence that Professor Dalton took or attempted to take credit for your work, or that he acted to exclude you as an author, or that he was even aware when the paper was first submitted for publication that there was an issue whether you should be an author. Accordingly, we do not find that Professor Dalton inappropriately took credit for your role in connection with the TCP chromophores."

Dalton's explanation to Cauce doesn't sound like a "communication failure" to me. In any case, everyone knows that the corresponding author (Dalton, not a graduate student) is ultimately responsible for ensuring that authorship of a paper complies with the journal's ethical standards.

For those who try to follow up on the 1967 notice in Retraction Watch, it should be noted that there is something funny going on with the original retraction notice for the 1967 paper. The retraction states,

“We have been informed by Dr. L. R. Dalton that some of the results
published in Inorganica Chimica Acta, 1, 1 ( 1967) were quoted without acknowledgment from an article by R. A. Zhitnikov and N. V. Kolesnikov (Fiz. Tverd. Tela, 7, 1175 (1965)) and that many of the experiments described were not actually performed.”

The actual page number of the article in Fizika Tverdogo Tela is 1157, not 1175, and Dalton's paper is on page 5, not page 1 of ICA volume 1. However, the important point is that Dalton did not plagiarize the Russian language version of this article. He plagiarized the English language version of the article, which is found in

R. A. Zhitnikov and N. V. Koleshnikov, “Paramagnetic resonance of free atoms of alkali metals Na K and Rb stabilized in a molecular matrix at liquid nitrogen temperatures,” Soviet Physics Solid State, 7(4), 927 (1967).

In addition to the EPR results, almost all of the text in the Soviet Physics Solid State article (over 1500 words) made it into Dalton’s article, usually verbatim and mostly in sequence.

For example:


"The letter A designates the capture location which occurs more often than the capture location B (in some experiments stabilization at the locations B did not occur, and the spectrum consisted of the lines of spectrum A alone). Spectrum B never occurred without spectrum A). The lines corresponding to the transition (1, -1<-->2, 0) are somewhat masked by the wing of the spectrum of the free radicals formed during condensation of the sample. This spectrum is more than an order of magnitude more intense than the sodium spectrum."


"The letter A designates the capture location which occurs more often than the alternate capture location B. In some experiments, stabilization at the location B did not occur and the spectrum consisted of the lines of spectrum A alone. However, spectrum B never occurred without spectrum A. The lines corresponding to the transition (1, <-->2 ,0) are somewhat masked by the wing of the spectrum of the free radicals formed during condensation of the sample. As can be seen from Figure 1, this spectrum is several orders of magnitude more intense than the sodium spectrum."

And on and on in many such passages...

Interested readers might also want to compare the spectra in these two papers.

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