|
|
| Samarium | |
| Electron Configuration | 2,8,18,24,8,2 |
| Electron Configuration | [Xe] 4f6 6s2 |
| Ground state | 7F0 |
| Atomic Volume | 19.95 g/cm3 |
| Electronegativity | 1.17 |
| Magnetic ordering | Antiferromagnetic |
| Mass magnetic susceptibility | 1.11 x 10-7 |
| Molar magnetic susceptibility | 1.669 x 10-8 |
| Speed of sound | 2130 m s-1 |
 Thermal Properties |
|
| Enthalpy of Atomization | 209 kJ mol-1 @25°C |
| Enthalpy of Fusion | 10.9 kJ mol-1 |
| Enthalpy of Vaporisation | 164.8 kJ mol-1 |
| Heat Capacity | 29.54 J mol-1 K-1 |
| Thermal Conductivity | 13.3 W m-1 K-1 |
| Thermal Expansion | 12.7 μm m-1 K-1 |
| Hardness |
|
| Brinell hardness | 441 MPa |
| Vickers hardness | 412 MPa |
| Elastic Properties |
|
| Bulk modulus | 37.8 GPa |
| Poisson ratio | 0.274 |
| Shear modulus | 19.5 GPa |
| Young's modulus | 49.7 GPa |
| Electrical Properties |
|
| Electrical resistivity | 9.4 x 10-7 Ω m |
| Electrical conductivity | No data. |
| Chemical Properties |
|
| Electrochemical Equivalent | 1.87 g Ah-1 |
| Electron Work Function | 2.7 eV |
| Valence Electron Potential (-eV) | 44.8 |
| Ionization Potential | |
 First
|
5.64 |
| Second
|
11.069 |
| Third
|
23.423 |
| Energy Levels |
|
| Kα1 (intensity 100) |
40.1181 KeV |
| Kα2 (intensity 50) |
39.5224 KeV |
| Kβ1 (intensity 22.4) |
45.413 KeV |
| Kβ2 (intensity 7.7) |
46.5438 KeV |
| Kβ3 (intensity 9.2) |
45.2836 KeV |
| Lα1 (intensity 100) |
5.6361 KeV |
| Lα2 (intensity 10) |
5.609 KeV |
| Lβ1 (intensity 46) |
6.2051 KeV |
| Lβ2 (intensity 17) |
6.586 KeV |
| Lβ3 (intensity 9) |
6.3165 KeV |
| Lβ4 (intensity 4) |
6.193 KeV |
| Lγ1 (intensity 6) |
7.178 KeV |
| Lγ2 (intensity 2.2) |
7.4625 KeV |
| Lγ3 (intensity 2) |
5.587 KeV |
| Ll (intensity 5) |
4.9929 KeV |
| Atomic Radii |
|
| Empirical
|
185 pm |
| Bohr Radius
|
238 pm |
| Covalent Radius
|
No data. |
| Van der Waals
|
No data. |
| Triple covalent
|
No data. |
| Metallic
|
180.4 pm |
| Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 2 | VII | 1.36 | 1.22 | |
| VIII | 1.41 | 1.27 | ||
| IX | 1.46 | 1.32 | ||
| 3 | VI | 1.098 | 0.958 | R |
| VII | 1.16 | 1.02 | E | |
| VIII | 1.219 | 1.079 | R | |
| IX | 1.272 | 1.132 | R | |
| XII | 1.38 | 1.24 | C | |
| R, From r3 vs V plots. |
| C, Calculated from bond length - bond strength equations. |
| E, Estimated. |
| *, Most Reliable. |
| M, From Metallic Oxides. |
| A, Ahrens (1952) Ionic radius. |
| P, Pauling's (1960) Crystal Radius. |
| Oxidation States |
|
| Main
|
Sm+3 |
| Other
|
Sm+2 |
Ionisation Energies (kJ mol-1)  |
|
| M - M+ |
543.3 |
| M+ - M2+ |
1068 |
| M2+ - M3+ |
2260 |
| M3+ - M4+ |
3990 |
| Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 1001 | 1106 | 1240 | (1421) | (1675) | (2061) |
| Crystal Structure |
|
| Structure
|
Trigonal |
 |
a = 362.1 pm |
| b = 362.1 pm | |
| c = 2625 pm | |
| α = 90° | |
| β = 90° | |
| γ = 120° | |