| Actinium | |
| Electrons per shell | 2,8,18,32,18,9,2 |
| Electron Configuration | [Rn] 6d1 7s2 ![]() |
| Ground state | 2D3/2 |
| Atomic Volume | 22.54 cm3 mol-1 |
| Electronegativity | 1.1 |
| Magnetic ordering | No data |
Thermal Properties |
|
| Enthalpy of Atomization | 301 kJ mol-1 @25°C |
| Enthalpy of Fusion | 14.2 kJ mol-1 |
| Enthalpy of Vaporisation | 293 kJ mol-1 |
| Heat Capacity | 27.2 J mol-1 K-1 |
| Thermal Conductivity | 12 W m-1 K-1 |
| Thermal Expansion | No data. |
| Critcal Temperature | No data. |
| Critcal Pressure | MPa |
| Adiabatic index | |
Electrical Properties |
|
| Electrical resistivity | No data. |
| Electrical conductivity | ? 106/cm Ω |
Chemical Properties |
|
| Electrochemical Equivalent | 2.82347 g Ah-1 |
| Valence Electron Potential (-eV) | 38.6 |
| Ionization Potential | |
| 5.17 | |
| 12.126 | |
Energy Levels |
|
| 90.884 KeV | |
| 87.67 KeV | |
| 102.85 KeV | |
| 12.652 KeV | |
| 12.5008 KeV | |
| 15.713 KeV | |
| 15.9261 KeV | |
| 15.1873 KeV | |
| 18.408 KeV | |
| 18.728 KeV | |
| 14.078 KeV | |
| 10.871 KeV | |
Atomic Radii |
|
| 195 pm | |
| No data. | |
| No data. | |
| No data. | |
| 140 pm | |
| No data. | |
Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 3 | VI | 1.26 | 1.12 | R |
| 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 |
|
| AcO, Ac+3 | |
Ionisation Energies (kJ mol-1) ![]() |
|
| 499 | |
| 1170 | |
| 1900 | |
| 4700 | |
| 6000 | |
| 7300 | |
| 9200 | |
| 10500 | |
| 11900 | |
| 15800 | |
Crystal Structure |
|
| Cubic close packed | |
![]() |
a = 567 pm |
| b = 567 pm | |
| c = 567 pm | |
| α = 90° | |
| β = 90° | |
| γ = 90° | |