| Erbium | |
| Electrons per shell | 2,8,18,30,8,2 |
| Electron Configuration | [Xe] 4f12 6s2 |
| Ground state | 3H6 |
| Atomic Volume | 18.4 cm3 mol-1 |
| Electronegativity | 1.24 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | 3.77 x 10-6 |
| Molar magnetic susceptibility | 6.30566 x 10-7 |
| Speed of sound | 2830 m s-1 |
 Thermal Properties |
|
| Enthalpy of Atomization | 314 kJ mol-1 @25°C |
| Enthalpy of Fusion | 17.2 kJ mol-1 |
| Enthalpy of Vaporisation | 280 kJ mol-1 |
| Heat Capacity | 28.12 J mol-1 K-1 |
| Thermal Conductivity | 14.5 W m-1 K-1 |
| Thermal Expansion | 12.2 μm m-1 K-1 |
| Hardness |
|
| Brinell hardness | 814 MPa |
| Vickers hardness | 589 MPa |
| Elastic Properties |
|
| Bulk modulus | 44.4 GPa |
| Poisson ratio | 0.237 |
| Shear modulus | 28.3 GPa |
| Young's modulus | 69.9 GPa |
| Electrical Properties |
|
| Electrical resistivity | 8.6 x 10-7 Ω m |
| Electrical conductivity | 0.0117 106/cm Ω |
| Chemical Properties |
|
| Electrochemical Equivalent | 2.0802 g Ah-1 |
| Valence Electron Potential (-eV) | 49 |
| Ionization Potential | |
 First
|
6.101 |
| Second
|
11.929 |
| Third
|
22.739 |
| Energy Levels |
|
| Kα1 (intensity 100) |
49.1277 KeV |
| Kα2 (intensity 50) |
48.2211 KeV |
| Kβ1 (intensity 24) |
55.681 KeV |
| Kβ2 (intensity 8.9) |
56.9286 KeV |
| Kβ3 (intensity 9.6) |
55.5145 KeV |
| Lα1 (intensity 100) |
6.9487 KeV |
| Lα2 (intensity 10) |
6.905 KeV |
| Lβ1 (intensity 42) |
7.8109 KeV |
| Lβ2 (intensity 17) |
8.189 KeV |
| Lβ3 (intensity 8) |
7.9375 KeV |
| Lβ4 (intensity 4) |
7.7437 KeV |
| Lγ1 (intensity 5.8) |
9.089 KeV |
| Lγ2 (intensity 2) |
9.3881 KeV |
| Lγ3 (intensity 2) |
7.056 KeV |
| Ll (intensity 4.5) |
6.1379 KeV |
| Atomic Radii |
|
| Empirical
|
175 pm |
| Bohr Radius
|
226 pm |
| Covalent Radius
|
No data. |
| Van der Waals
|
No data. |
| Triple covalent
|
No data. |
| Metallic
|
176.1 pm |
| Oxidation States |
|
| Main
|
Er+3 |
| Other
|
|
Ionisation Energies (kJ mol-1)  |
|
| M - M+ |
588.7 |
| M+ - M2+ |
1151 |
| M2+ - M3+ |
2194 |
| M3+ - M4+ |
4115 |
| Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 1504 | 1663 | (1885) | (2163) | (2552) | (3132) |
| Crystal Structure |
|
| Structure
|
Hexagonal close packed |
 |
a = 355.88 pm |
| b = 355.88 pm | |
| c = 558.74 pm | |
| α = 90° | |
| β = 90° | |
| γ = 120° | |