| Thorium | |
| Electrons per shell | 2,8,18,32,18,10,2 |
| Electron Configuration | [Rn] 6d2 7s2 |
| Ground state | 3F2 |
| Atomic Volume | 19.9 cm3 mol-1 |
| Electronegativity | 1.3 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | 5.3 x 10-9 |
| Molar magnetic susceptibility | 1.23 x 10-9 |
| Speed of sound | 2490 m s-1 |
 Thermal Properties |
|
| Enthalpy of Atomization | 565 kJ mol-1 @25°C |
| Enthalpy of Fusion | 19.2 kJ mol-1 |
| Enthalpy of Vaporisation | 513.7 kJ mol-1 |
| Heat Capacity | 26.230 J mol-1 K-1 |
| Thermal Conductivity | 54.0 W m-1 K-1 |
| Thermal Expansion | 11.0 μm m-1 K-1 |
| Hardness |
|
| Brinell hardness | 400 MPa |
| Mohs hardness | 3.0 |
| Vickers hardness | 350 MPa |
| Elastic Properties |
|
| Bulk modulus | 54 GPa |
| Poisson ratio | 0.27 |
| Shear modulus | 31 GPa |
| Young's modulus | 79 GPa |
| Electrical Properties |
|
| Electrical resistivity | 1.5 x 10-7 Ω m |
| Electrical conductivity | 0.0653 106/cm Ω |
| Chemical Properties |
|
| Electrochemical Equivalent | 2.1643 g Ah-1 |
| Electron Work Function | 3.41 eV |
| Valence Electron Potential (-eV) | 59.3 |
| Ionization Potential | |
 First
|
6.08 |
| Second
|
11.504 |
| Third
|
20.003 |
| Energy Levels |
|
| Kα1 (intensity 0) |
93.35 KeV |
| Kα2 (intensity 0) |
89.953 KeV |
| Kβ1 (intensity 0) |
105.609 KeV |
| Lα1 (intensity 100) |
12.9687 KeV |
| Lα2 (intensity 10) |
12.8096 KeV |
| Lβ1 (intensity 38) |
16.2022 KeV |
| Lβ2 (intensity 14) |
15.6237 KeV |
| Lβ3 (intensity 2) |
16.4212 KeV |
| Lβ4 (intensity 2) |
15.6385 KeV |
| Lγ1 (intensity 8) |
18.9825 KeV |
| Lγ2 (intensity 2.7) |
19.2987 KeV |
| Lγ3 (intensity 2) |
14.505 KeV |
| Ll (intensity 6) |
11.1189 KeV |
| Atomic Radii |
|
| Empirical
|
180 pm |
| Bohr Radius
|
No data. |
| Covalent Radius
|
No data. |
| Van der Waals
|
No data. |
| Triple covalent
|
136 pm |
| Metallic
|
179 pm |
| Oxidation States |
|
| Main
|
Th+4 |
| Other
|
Th+2, Th+3 |
Ionisation Energies (kJ mol-1)  |
|
| M - M+ |
587 |
| M+ - M2+ |
1110 |
| M2+ - M3+ |
1978 |
| M3+ - M4+ |
2780 |
| Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 2633 | 2907 | 3248 | 3683 | 4259 | 5055 |
| Crystal Structure |
|
| Structure
|
Cubic close packed |
 |
a = 508.42 pm |
| b = 508.42 pm | |
| c = 508.42 pm | |
| α = 90° | |
| β = 90° | |
| γ = 90° | |