| Share


meitnerium (mĪtnĭrˈēəm) [key], artificially produced radioactive chemical element; symbol Mt; at. no. 109; mass number of most stable isotope 276; m.p., b.p., sp. gr., and valence unknown. Situated in Group 9 of the periodic table it is expected to have properties similar to those of iridium.

In 1982 a German research team led by P. Armbruster and G. Münzenberg at the Institute for Heavy Ion Research at Darmstadt bombarded bismuth-209 atoms with iron-58 ions. On the tenth day of the experiment, one atom was unambiguously identified as an isotope of element 109 with mass number 266 and a half-life of 3.4 msec. The Germans suggested the name meitnerium to honor the Austrian-Swedish physicist and mathematician Lise Meitner. This name was recognized internationally in 1997. The most stable isotope of meitnerium, meitnerium-276, has a half-life of 0.72 sec.

See also synthetic elements; transuranium elements.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

More on meitnerium from Infoplease:

See more Encyclopedia articles on: Compounds and Elements

Premium Partner Content
HighBeam Research
Documents Images and Maps Reference
(from Newspapers, Magazines, Journals, Newswires, Transcripts and Books)

Research our extensive archive of more than 80 million articles from 6,500 publications.

Additional search results provided by HighBeam Research, LLC. © Copyright 2005. All rights reserved.

24 X 7

Private Tutor

Click Here for Details
24 x 7 Tutor Availability
Unlimited Online Tutoring
1-on-1 Tutoring