| 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 |
| Critcal Temperature | No data. |
| Critcal Pressure | No data. |
| Adiabatic index | No data. |
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 | |
| 6.08 | |
| 11.504 | |
| 20.003 | |
Energy Levels |
|
| 93.35 KeV | |
| 89.953 KeV | |
| 105.609 KeV | |
| 12.9687 KeV | |
| 12.8096 KeV | |
| 16.2022 KeV | |
| 15.6237 KeV | |
| 16.4212 KeV | |
| 15.6385 KeV | |
| 18.9825 KeV | |
| 19.2987 KeV | |
| 14.505 KeV | |
| 11.1189 KeV | |
Atomic Radii |
|
| 180 pm | |
| No data. | |
| No data. | |
| No data. | |
| 136 pm | |
| 179 pm | |
Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 4 | VI | 1.08 | 0.94 | C |
| VIII | 1.19 | 1.05 | RC | |
| IX | 1.23 | 1.09 | * | |
| X | 1.27 | 1.13 | E | |
| XI | 1.32 | 1.18 | C | |
| XII | 1.35 | 1.21 | 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 |
|
| Th+4 | |
| Th+2, Th+3 | |
Ionisation Energies (kJ mol-1) ![]() |
|
| 587 | |
| 1110 | |
| 1978 | |
| 2780 | |
Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 2633 | 2907 | 3248 | 3683 | 4259 | 5055 |
Crystal Structure |
|
| Cubic close packed | |
![]() |
a = 508.42 pm |
| b = 508.42 pm | |
| c = 508.42 pm | |
| α = 90° | |
| β = 90° | |
| γ = 90° | |