| Discovery date | 1952 |
| Discovered by | Albert Ghiorso and colleagues |
| Origin of the name | Einsteinium is named after the renowned physicist Albert Einstein. |
| Allotropes |
|
Es
Einsteinium
99
[252]
| Group | Actinides | Melting point | 860°C, 1580°F, 1133 K |
| Period | 7 | Boiling point | Unknown |
| Block | f | Density (g cm−3) | Unknown |
| Atomic number | 99 | Relative atomic mass | [252] |
| State at 20°C | Solid | Key isotopes | 252Es |
| Electron configuration | [Rn] 5f117s2 | CAS number | 7429-92-7 |
| ChemSpider ID | 22356 | ChemSpider is a free chemical structure database | |
Image explanation
The design is inspired by the work of Albert Einstein and images collected from early particle accelerators, such as those at Cern and Fermilab. The arrows are from one of these annotated (and unattributed) images indicating the direction of collisions. An abstracted ‘collider’ pattern is shown in the background.
Appearance
A radioactive metal, only a few milligrams of which are made each year.
Uses
Einsteinium has no uses outside research.
Biological role
Einsteinium has no known biological role. It is toxic due to its radioactivity.
Natural abundance
Einsteinium can be obtained in milligram quantities from the neutron bombardment of plutonium in a nuclear reactor.
Einsteinium was discovered in the debris of the first thermonuclear explosion which took place on a Pacific atoll, on 1 November 1952. Fall-out material, gathered from a neighbouring atoll, was sent to Berkeley, California, for analysis. There it was examined by Gregory Choppin, Stanley Thompson, Albert Ghiorso, and Bernard Harvey. Within a month they had discovered and identified 200 atoms of a new element, einsteinium, but it was not revealed until 1955.
The einsteinium had formed when some uranium atoms had captured several neutrons and gone through a series of capture and decay steps resulting in einsteinium-253, which has a half-life of 20.5 days.
By 1961, enough einsteinium had been collected to be visible to the naked eye, and weighed, although it amounted to mere 10 millionths of a gram.
| Atomic radius, non-bonded (Å) | 2.45 | Covalent radius (Å) | 1.65 |
| Electron affinity (kJ mol−1) | Unknown |
Electronegativity (Pauling scale) |
Unknown |
|
Ionisation energies (kJ mol−1) |
1st
619.44
2nd
1158
3rd
-
4th
-
5th
-
6th
-
7th
-
8th
-
|
||
| Common oxidation states | 3 | ||||
| Isotopes | Isotope | Atomic mass | Natural abundance (%) | Half life | Mode of decay |
| 252Es | 252.083 | - | 1.29 y | α | |
| - | EC | ||||
|
Specific heat capacity (J kg−1 K−1) |
Unknown | Young's modulus (GPa) | Unknown | |||||||||||
| Shear modulus (GPa) | Unknown | Bulk modulus (GPa) | Unknown | |||||||||||
| Vapour pressure | ||||||||||||||
| Temperature (K) |
|
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| Pressure (Pa) |
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| Listen to Einsteinium Podcast |
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Transcript :
Chemistry in its element: einsteinium(Promo) You're listening to Chemistry in its element brought to you by Chemistry World, the magazine of the Royal Society of Chemistry. (End promo) Meera Senthilingam This week, there's no need to even guess who this element is named after, but it's more than fame that got this element its name - Brian Clegg Brian Clegg At first glance there's nothing odd about naming element 99 in the periodic table 'einsteinium'. After all, Einstein is the most famous scientist that has ever lived. Yet fame is not usually a good enough reason to make it into the exclusive club of the elements. Although the likes of Lawrence, Rutherford, Seaborg and Bohr have been honoured, there's no Newton or Laplace, Dalton or Feynman. Not even the new saint of science, Darwin. The clue to Einstein's position here is that many of those with elements named after them played a fundamental role in our understanding of atomic structure. There is the odd highly doubtful case - but Einstein isn't one of them. He's not on the table because he's famous, but because he was responsible not only for relativity but for laying some of the foundations of quantum theory, which would explain how atoms interact. What's more, his study of Brownian motion was the first work to give serious weight to the idea that atoms existed at all. For such a great figure, einsteinium verges on being an also-ran. It's one of the actinides, the second of the floating rows of the periodic table that are numerically squeezed between radium and lawrencium. Although only tiny amounts of it have ever been made, it's enough to determine that like its near neighbours in the table it is a silvery metal. Around twenty isotopes have been produced with half lives - that's the time it takes half of the substance to decay - ranging from seconds to over a year, though the most common isotope, einsteinium 253 only has a 20 day half life. Apart from its name, what makes einsteinium stand out is the way it was first produced. When the Soviet Union developed its own atomic bomb, America felt it had to have something even more powerful to keep ahead. Using an atomic bomb as a trigger, the new type of device, referred to as a 'Super' would apply so much heat and pressure to the hydrogen isotope deuterium that the atoms would fuse together, just as they do in the Sun. It was to be the first thermonuclear weapon. The H bomb. After months of technical testing of components, the first thermonuclear bomb was ready to be tried out at a remote island location, Elugelab on the Eniwetok Atoll in the South Pacific. Like the innocently named Little Boy and Fat Man - the bombs that were dropped on Hiroshima and Nagasaki - this bomb had a nickname. It was called 'the sausage' because of its long cylindrical shape. When the bomb exploded on November the first, 1952, it produced an explosion with the power of over 10 million tonnes of TNT - five hundred times the destructive power of the Nagasaki explosion, totally destroying the tiny island. This was very much a test device - weighing over 80 tons and requiring a structure around 50 feet high to support it, meaning that it could never have been deployed - but it proved, all too well, the capability of the thermonuclear weapon. And in the moments of that intense explosion it produced a brand new element. As part of the aftermath of the test, tonnes of material from the fallout zone were sent to Berkeley, the home of created elements, for testing. There among the ash and charred remains of coral were found a couple of hundred atoms of element 99, later to be called einsteinium. Such was the secrecy surrounding the test, the element's discovery was not made public for three years. It was in Physical Review of August the first 1955 that the discoverer Albert Ghiorso and his colleagues first suggested the name einsteinium. In the intense heat and pressure of the explosion, some of the uranium in the fission bomb that was used to trigger the thermonuclear inferno had been bombarded with vast numbers of neutrons, producing a scattering of heavier atoms. At the same time, neutrons in the newly formed atoms' nuclei underwent beta decay, producing an electron and a proton. So instead of just getting heavier and heavier uranium isotopes, the result was an alchemist's delight of transmutation, ending up with einsteinium 253. Not surprisingly, this production method is not the norm. Now, when einsteinium is required, plutonium is bombarded with neutrons in a reactor for several years until it is has taken on enough extra neutrons in the nucleus to pump it up to einsteinium. This only produces tiny amounts - in fact after its discovery it took a good 9 years before enough einsteinium had been produced to be able to see it. In part the tiny quantities of einsteinium that have been made reflect the difficulty of producing it. But it also receives the sad accolade of having no known uses. There really isn't any reason for making einsteinium, except as a waypoint on the route to producing something else. It's an element without a role in life. We started by thinking of why Einstein might be honoured by appearing in the periodic table. It's true that Albert Einstein made a huge contribution to the understanding of atoms and atomic structure. But it's hard not to see his presence in einsteinium being more because of the application of his iconic equation E=mc2 that he hated. The conversion of mass to energy in the world's most destructive weapons. If Einstein can be considered the father of the nuclear explosion, then einsteinium will always be the child of the bomb. Meera Senthilingam That's quite a birth to come from an atomic bomb. That was Brian Clegg with the explosive origins of einsteinium. Now next week we've got a very useful element with many roles in life, including multiple ways of protecting our health. Simon Cotton It is also used in sunscreens, since it is a very opaque white and also very good at absorbing UV light. When UV light falls upon it, it generates free electrons that react with molecules on the surface, forming very reactive organic free radicals. Now you don't want these radicals on your skin, so the TiO2 used in sunscreens is coated with a protective layer of silica or alumina. In other situations, these radicals can be a good thing, as they can kill bacteria. You can put very thin coatings of TiO2 onto glass (or other substances like tiles); these are being tested in hospitals, as a way of reducing infections. Meera Senthilingam And Simon Cotton will be bringing us more of the uses and properties of titanium in next week's Chemistry in its element. Until then, I'm Meera Senthilingam and thank you for listening. (Promo) Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.com. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.org/elements. (End promo)
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Visual Elements images and videos
© Murray Robertson 1998-2017.
W. M. Haynes, ed., CRC Handbook of Chemistry and Physics, CRC Press/Taylor and Francis, Boca Raton, FL, 95th Edition, Internet Version 2015, accessed December 2014.
Tables of Physical & Chemical Constants, Kaye & Laby Online, 16th edition, 1995. Version 1.0 (2005), accessed December 2014.
J. S. Coursey, D. J. Schwab, J. J. Tsai, and R. A. Dragoset, Atomic Weights and Isotopic Compositions (version 4.1), 2015, National Institute of Standards and Technology, Gaithersburg, MD, accessed November 2016.
T. L. Cottrell, The Strengths of Chemical Bonds, Butterworth, London, 1954.
John Emsley, Nature’s Building Blocks: An A-Z Guide to the Elements, Oxford University Press, New York, 2nd Edition, 2011.
Thomas Jefferson National Accelerator Facility - Office of Science Education, It’s Elemental - The Periodic Table of Elements, accessed December 2014.
Periodic Table of Videos, accessed December 2014.
Derived in part from material provided by the British Geological Survey © NERC.
Elements 1-112, 114, 116 and 117 © John Emsley 2012. Elements 113, 115, 117 and 118 © Royal Society of Chemistry 2017.
Produced by The Naked Scientists.
Created by video journalist Brady Haran working with chemists at The University of Nottingham.
© Murray Robertson 1998-2017.
Data
W. M. Haynes, ed., CRC Handbook of Chemistry and Physics, CRC Press/Taylor and Francis, Boca Raton, FL, 95th Edition, Internet Version 2015, accessed December 2014.
Tables of Physical & Chemical Constants, Kaye & Laby Online, 16th edition, 1995. Version 1.0 (2005), accessed December 2014.
J. S. Coursey, D. J. Schwab, J. J. Tsai, and R. A. Dragoset, Atomic Weights and Isotopic Compositions (version 4.1), 2015, National Institute of Standards and Technology, Gaithersburg, MD, accessed November 2016.
T. L. Cottrell, The Strengths of Chemical Bonds, Butterworth, London, 1954.
Uses and properties
John Emsley, Nature’s Building Blocks: An A-Z Guide to the Elements, Oxford University Press, New York, 2nd Edition, 2011.
Thomas Jefferson National Accelerator Facility - Office of Science Education, It’s Elemental - The Periodic Table of Elements, accessed December 2014.
Periodic Table of Videos, accessed December 2014.
Supply risk data
Derived in part from material provided by the British Geological Survey © NERC.
History text
Elements 1-112, 114, 116 and 117 © John Emsley 2012. Elements 113, 115, 117 and 118 © Royal Society of Chemistry 2017.
Podcasts
Produced by The Naked Scientists.
Periodic Table of Videos
Created by video journalist Brady Haran working with chemists at The University of Nottingham.
