| Rhodium | |
| Electrons per shell | 2,8,18,16,1 |
| Electron Configuration | [Kr] 4d8 5s1 ![]() |
| Ground state | 4F9/2 |
| Atomic Volume | 8.3 cm3 mol-1 |
| Electronegativity | 2.28 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | 1.32 x 10-8 |
| Molar magnetic susceptibility | 1.358 x 10-9 |
| Speed of sound | 4700 m s-1 |
Thermal Properties |
|
| Enthalpy of Atomization | 556.5 kJ mol-1 @25°C |
| Enthalpy of Fusion | 21.55 kJ mol-1 |
| Enthalpy of Vaporisation | 494.3 kJ mol-1 |
| Heat Capacity | 24.98 J mol-1 K-1 |
| Thermal Conductivity | 150 W m-1 K-1 |
| Thermal Expansion | 8.2 μm m-1 K-1 |
| Critcal Temperature | No data. |
| Critcal Pressure | No data. |
| Adiabatic index | No data. |
Hardness |
|
| Brinell hardness | 1100 MPa |
| Mohs hardness | 6.0 |
| Vickers hardness | 1246 MPa |
Elastic Properties |
|
| Bulk modulus | 380 GPa |
| Poisson ratio | 0.26 |
| Shear modulus | 150 GPa |
| Young's modulus | 275 GPa |
Electrical Properties |
|
| Electrical resistivity | 4.3 x 10-8 Ω m |
| Electrical conductivity | 0.211 106/cm Ω |
Chemical Properties |
|
| Electrochemical Equivalent | .2798 g Ah-1 |
| Electron Work Function | 4.98 eV |
| Valence Electron Potential (-eV) | 64 |
| Ionization Potential | |
| 7.46 | |
| 18.08 | |
| 31.06 | |
| Incompatibilities | Chlorine trifluoride (ClF3), oxygen difluoride (OF2). |
Flammability |
|
Energy Levels |
|
| 20.2161 KeV | |
| 20.0737 KeV | |
| 22.7236 KeV | |
| 23.1683 KeV | |
| 22.6952 KeV | |
| 2.69674 KeV | |
| 2.69205 KeV | |
| 2.83441 KeV | |
| 3.0013 KeV | |
| 2.9139 KeV | |
| 2.8903 KeV | |
| 3.1438 KeV | |
| 3.3612 KeV | |
| 2.519 KeV | |
| 2.3731 KeV | |
Atomic Radii |
|
| 135 pm | |
| 173 pm | |
| 135 pm | |
| No data. | |
| 106 pm | |
| 134 pm | |
Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 3 | VI | 0.805 | 0.665 | R |
| 4 | VI | 0.74 | 0.6 | RM |
| 5 | VI | 0.69 | 0.55 | |
| 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 |
|
| Rh+3 | |
| Rh-1, Rh0, Rh+1, Rh+2, Rh+4, Rh+5, Rh+6 | |
Ionisation Energies (kJ mol-1) ![]() |
|
| 720 | |
| 1744 | |
| 2997 | |
| 4400 | |
| 6500 | |
| 8200 | |
| 10100 | |
| 12200 | |
| 14200 | |
| 22000 | |
Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 2288 | 2496 | 2749 | 3063 | 3405 | 3997 |
Crystal Structure |
|
| Cubic close packed | |
![]() |
a = 380.34 pm |
| b = 380.34 pm | |
| c = 380.34 pm | |
| α = 90° | |
| β = 90° | |
| γ = 90° | |