Another Research Director Bites the Dust

From Physics Today on September 23, 2009

Physics Today: Peter Chen, the head of research at the Swiss Federal Institute of Technology Zürich (ETH Zürich) has resigned after an investigation (at his request) into two papers published in the Journal of Chemical Physics and a doctoral thesis from his research group turned out to contain falsified data. The investigation could not conclude who was responsible for the falsifications.

Peter Chen (Credit: ETH Zürich)In a statement released by ETH Zürich the institute said "out of respect for ETH Zürich and the function as head of research, Peter Chen has acknowledged his responsibility and decided to step down as Vice President at the end of September 2009."

"Scientific misconduct jeopardizes the very core of research and must carry consequences," says ETH Zürich President Ralph Eichler. "This has been the case here and the matter also shows that the established control mechanisms for research really do work."

The research projects affected hail from the field of basic research in chemistry at ETH Zürich and were published in 2000 by members of the team then headed by Chen. He has been professor of physical-organic chemistry since 1994 and the vice-president of research and corporate relations since 2007.

The papers under suspicion concerned results relating to the spectroscopic structural clarification of hydrocarbon radicals: short-lived chemical compounds that are formed during combustion processes. The number of citations accrued by the two papers is 66, which is quite a large score.

Intensive search for discrepancies

The experiments were conducted with the so-called “zero-kinetic-energy photoelectron spectroscopy” method, a high-resolution version of photoelectron spectroscopy. The method can be used, amongst other things, to analyze highly reactive or instable compounds. The measurements include electrons that break away from the molecule under examination after it has absorbed light. The spectra determined as a result can then be used to analyze the geometric structure and dynamics of the compounds.

However, after the papers were published, other research groups working in the same field obtained significantly different results.

Chen’s group set about seeking an explanation for the discrepancies in conjunction with a former post-doctoral researcher’s group. The discrepancies initially involved the ionization energy of alkyl radicals. Ionization energy means any energy needed to separate the least stable electron from an atom in its basic state.

A disturbing conclusion

Not only was the attempt to reproduce the values measured unsuccessful, but other inconsistencies led Chen to suspect foul play. He called upon ETH Zürich's executive board to appoint a scientific board of inquiry to clarify the irregularities at the beginning of January 2009. At the same time, he and his co-authors withdrew the first publication.

Five internationally renowned professors (three external ones and two from ETH Zürich) were appointed to the commission. They scrutinized the studies in question, repeated the processes used at the time where possible and interviewed the three authors involved in the experiments: the doctoral and post-doctoral students at the time and Chen.

The commission concluded that some of the data had been falsified. For example, certain diagrams involving representations of the measured spectra often contained identical patterns from static, i.e. technically unavoidable signals without any discernible information content. The fact that some of the noise patterns recur in an identical fashion is virtually impossible, which suggests they were added to the diagrams afterwards says their final report. Moreover, repeating the experiments revealed that some of the lines apparently measured within the spectra actually did not exist.

In addition, the relevant lab books and most of the raw data for the experiments are missing, limiting the likelihood that the experiment could be successfully replicated.

Resolution

All of the people involved in the experiments categorically deny having carried out the falsifications; however, they all agree that the data was falsified.

Consequently, the second publication with the fake data was withdrawn.

At this point, the author of the doctoral thesis initially withdrew his thesis on his own accord, but retracted the withdrawal later.

ETH Zürich has postponed the planned publication of the commission’s report for the time being for legal reasons associated with the doctoral thesis.

After receiving the report ETH Zürich's executive board conducted its own investigation to form its own opinion. "The commission resolved the matter objectively and I am much obliged to them in the name of ETH Zürich," says Eichler. “Unfortunately, there is now no legal way of finding out for sure who was responsible for the falsifications," he added.


Chen assumes responsibility

As the current vice-president responsible for quality assurance in research, Chen felt that the incident had compromised his effectiveness, and decided to step down.

"Peter Chen is an impressive researcher and a highly valued member of our board in every respect," stresses Eichler. "We very much regret to lose such an accomplished leader, but we are happy that he’ll remain in our midst as a model colleague, outstanding scientist and professor."