The mineralogy of Einsteinium

About Einsteinium
Einsteinium is a radioactive transuranic element that has only been produced in nuclear reactors. It is possible that some einsteinium and other transuranic elements were created in the natural nuclear reactor in Oklo, Gabon.

General Properties
Symbol:	Es
Atomic Number:	99
Standard atomic weight (A_r):	[252]
Electron configuration:	[Rn] 5f¹¹ 7s²

Photos

300 micrograms of Einsteinium 253

Atomic Properties
Electronegativity (Pauling scale):	1.3
1st Ionization energy:	619 kJ/mol
Oxidation States:	2,3

Physical Properties
Standard State:	solid
Melting Point:	1133 K
Metal/Non-Metal:	actinoid

Main isotopes of Einsteinium
Isotope	% in Nature	Half Life	Decay type	Decay product
²⁵²Es	synthetic	471.7d	α	²⁴⁸Bk
			ε	²⁵²Cf
			β−	²⁵²Fm
²⁵³Es	synthetic	20.47d	Spontaneous fission
²⁵³Es	synthetic	20.47d	α	²⁴⁹Bk
²⁵⁴Es	synthetic	275.7d	ε	²⁵⁴Cf
			β−	²⁵⁴Fm
			α	²⁵⁰Bk
²⁵⁵Es	synthetic	39.8d	β−	²⁵⁵Fm
			α	²⁵¹Bk
			Spontaneous fission

Other Information
Year Discovered:	1952
Discovered By:	Lawrence Berkeley National Laboratory
Named For:	Albert Einstein
CPK color coding:	#B31FD4
External Links:	Wikipedia WebElements Los Alamos National Laboratory Theodore Gray's PeriodicTable.com

Simple Compounds
Fluorides	einsteinium trifluoride	EsF₃	+3
Chlorides	einsteinium dichloride	EsCl₂	+2
Chlorides	einsteinium trichloride	EsCl₃	+3
Bromides	einsteinium tribromide	EsBr₃	+3
Iodides	einsteinium diiodide	EsI₂	+2
Iodides	einsteinium triiodide	EsI₃	+3
Oxides	dieinsteinium trioxide	Es₂O₃	+3

Periodic Table

2He

3Li

4Be

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Default Categories CPK Electronegativity Atomic Radius Lowest Oxidation Highest Oxidation Crustal Abundance Goldschmidt Mineral Species

Californium << Einsteinium >> Fermium

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Constants and physical property data from:

Lide, David R. - Ed. (2005) CRC Handbook of Chemistry and Physics - A Ready-Reference Book of Chemical and Physical Data (85th ed.). CRC Press.
National Physical Laboratory (2005) Kaye and Laby Online (discontinued). https://web.archive.org/web/20190506031327/http://www.kayelaby.npl.co.uk/
Kaye, G. W. C.; Laby, T. H. (n.d.) Tables of Physical and Chemical Constants and some Mathematical Functions. Longmans, Green, and Co.
Greenwood, N.N.; Earnshaw, A. (1997) Chemistry of the Elements (2nd ed.). Butterworth–Heinemann.
Ahrens, Thomas J. - Ed. (1995) Global Earth Physics - A Handbook of Physical Constants - AGU Reference Shelf No. 1. American Geophysical Union.
Railsback, L. Bruce (2003) An earth scientist's periodic table of the elements and their ions. Geology, 31 (9) 737 doi:10.1130/g19542.1
Emsley, John (2001) Nature's Building Blocks - An A-Z Guide to the Elements. Oxford University Press, Oxford.

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