technetium

29 September 2009

Technetium, element 43, is the first element to be artificially produced; it only occurs naturally in trace amounts as a product of uranium fission. The name is from the Greek τεχνητόςtechnetos, meaning artificial. Discoverers Carlo Perrier and Emilio Segrè write in the 4 January 1947 issue of Nature:

We would like to propose the name of “technetium,” from the Greek τεχνητός, artificial, in recognition of the fact that technetium is the first artificially made element. The corresponding chemical symbol should be “Tc.”

Technetium’s existence and chemical properties were predicted by Mendeleev in the early 19th century, but no one could actually find the element, despite numerous attempts and false discoveries over the years. Then in 1925, German chemists Walter Noddack, Otto Berg and Ida Tacke claimed to have created technetium by bombarding columbite with electrons and examining x-ray spectrographs of the process for the signature of the element. They named the product masurium; Noddack was from the Masuria region of Poland. From the Glasgow Herald, 16 June 1925:

These new elements have been named by their discoverers “Masurium,” after the Masurian Lake region, and “Rhenium,” after the Rhineland.

But their experiment could not be replicated and their discovery was not universally accepted.

Then in 1937 Perrier and Segrè, working at the University of Palermo, rediscovered technetium in a sample of irradiated molybdenum foil they had obtained from the cyclotron at the University of California, Berkeley. The results were published in Nature ten years later. (There was a little scuffle in Europe at about that time that presumably disrupted the publication schedule.) So official discovery and naming rights went to Perrier and Segrè.


Oxford English Dictionary, technetium, 2nd Edition, 1989.

Oxford English Dictionary, masurium, 3rd Edition, March 2001.