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Element: Erbium

General data

Element nameErbium
Chemical symbolEr
Atomic number Z68
Year discovered1843
Standard state (25°C)Solid
CategoryLanthanide
Blockf
Atomic mass167.26
CPK colorno data

Physical properties

Melting point1802 K (1529 °C)
Boiling point3141 K (2868 °C)
Density9.07 g/cm³

Energy properties

First ionization energy6.108 eV
Electron affinityno data

Atomic structure

Protons68 (Atomic number)
Neutrons (Er-166, most abundant isotope)98
Electrons68
Electron configuration[Xe] 6s² 4f¹²
Oxidation states+3
Electronegativity (Pauling)1.24
Atomic radius (van der Waals)235 pm

Ionization energies - NIST ASD (68 states)

StateChargeIoniz. energy (eV)Type
Er I0+6.1077 ± 0.001measured
Er II1+11.916 ± 0.02semi-empirical
Er III2+22.7 ± 0.03semi-empirical
Er IV3+42.42 ± 0.04semi-empirical
Er V4+65.1 ± 0.4semi-empirical
Er VI5+96 ± 5calculated
Er VII6+114 ± 6calculated
Er VIII7+131 ± 7calculated
Er IX8+158 ± 8calculated
Er X9+177 ± 9calculated
Er XI10+201 ± 10calculated
Er XII11+235 ± 11calculated
Er XIII12+268 ± 14calculated
Er XIV13+290 ± 15calculated
Er XV14+311 ± 16calculated
Er XVI15+345 ± 17calculated
Er XVII16+381 ± 19calculated
Er XVIII17+415 ± 21calculated
Er XIX18+450 ± 22calculated
Er XX19+486 ± 25calculated
Er XXI20+520 ± 30calculated
Er XXII21+555 ± 5calculated
Er XXIII22+770 ± 4calculated
Er XXIV23+810 ± 4calculated
Er XXV24+853 ± 4calculated
Er XXVI25+899 ± 4calculated
Er XXVII26+943 ± 4calculated
Er XXVIII27+989 ± 4calculated
Er XXIX28+1046 ± 4calculated
Er XXX29+1092 ± 4calculated
Er XXXI30+1142 ± 4calculated
Er XXXII31+1188 ± 4calculated
Er XXXIII32+1370 ± 4calculated
Er XXXIV33+1416 ± 5calculated
Er XXXV34+1468 ± 5calculated
Er XXXVI35+1516 ± 5calculated
Er XXXVII36+1625 ± 5calculated
Er XXXVIII37+1678 ± 4calculated
Er XXXIX38+1803 ± 4calculated
Er XL39+1858.5 ± 0.5semi-empirical
Er XLI40+3157 ± 4calculated
Er XLII41+3265 ± 4calculated
Er XLIII42+3381 ± 4calculated
Er XLIV43+3505 ± 4calculated
Er XLV44+3624 ± 4calculated
Er XLVI45+3742 ± 4calculated
Er XLVII46+3916 ± 4calculated
Er XLVIII47+4038 ± 4calculated
Er XLIX48+4170 ± 4calculated
Er L49+4294 ± 4calculated
Er LI50+4639 ± 4calculated
Er LII51+4748 ± 4calculated
Er LIII52+4866 ± 4calculated
Er LIV53+4978 ± 5calculated
Er LV54+5329 ± 5calculated
Er LVI55+5455 ± 5calculated
Er LVII56+5695 ± 5calculated
Er LVIII57+5815 ± 6calculated
Er LIX58+12918 ± 6calculated
Er LX59+13217 ± 7calculated
Er LXI60+13548 ± 10calculated
Er LXII61+13855 ± 12calculated
Er LXIII62+15146 ± 15calculated
Er LXIV63+15511 ± 19calculated
Er LXV64+15971 ± 24calculated
Er LXVI65+16274.56 ± 0.12calculated
Er LXVII66+65848.24 ± 0.12calculated
Er LXVIII67+67241.48 ± 0.07calculated

Value type as given by NIST ASD: measured - from evaluated experimental data; calculated - from ab initio calculations (mostly highly ionised atoms that have not been measured; for the simplest ones, e.g. H I, the calculation is more accurate than measurement); semi-empirical - from interpolation, extrapolation or another semi-empirical method.

Photos

Photo of the element: Erbium (Er)
© images-of-elements.com (CC BY 3.0)

Isotopes (38)

ANHalf-lifeDecay
Er-14375unknownEC/β⁺
Er-14476unknownEC/β⁺
Er-145770.9 sEC/β⁺
Er-146781.7 sEC/β⁺
Er-147793.2 sEC/β⁺
Er-148804.6 sEC/β⁺
Er-149814 sEC/β⁺
Er-1508218.7 sEC/β⁺
Er-1518323.5 sEC/β⁺
Er-1528410.2 sα
Er-1538537.1 sα
Er-154863.73 minEC/β⁺
Er-155875.3 minEC/β⁺
Er-1568819.5 minEC/β⁺
Er-1578918.65 minEC/β⁺
Er-158902.26 hEC
Er-1599136 minEC/β⁺
Er-1609228.58 hEC
Er-161933.21 hEC/β⁺
Er-16294stable-
Er-1639575.0 minEC/β⁺
Er-16496stable-
Er-1659710.36 hEC
Er-16698stable-
Er-16799stable-
Er-168100stable-
Er-1691019.39 dβ⁻
Er-170102stable-
Er-1711037.516 hβ⁻
Er-17210449.3 hβ⁻
Er-1731051.4 minβ⁻
Er-1741063.2 minβ⁻
Er-1751071.2 minβ⁻
Er-176108unknownβ⁻
Er-177109unknownβ⁻
Er-178110unknownβ⁻
Er-179111unknownβ⁻
Er-180112unknownβ⁻

Data sources

More about the data sources