| Thallium | |
| Electrons per shell | 2,8,18,32,18,3 |
| Electron Configuration | [Xe] 4f14 5d10 6s2 6p1 |
| Ground state | 2°1/2 |
| Atomic Volume | 17.2 cm3 mol-1 |
| Electronegativity | 1.62 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | -3 x 10-9 |
| Molar magnetic susceptibility | -6.13 x 10-10 |
| Speed of sound | 818 m s-1 |
 Thermal Properties |
|
| Enthalpy of Atomization | 179.9 kJ mol-1 @25°C |
| Enthalpy of Fusion | 4.31 kJ mol-1 |
| Enthalpy of Vaporisation | 166.1 kJ mol-1 |
| Heat Capacity | 26.32 J mol-1 K-1 |
| Thermal Conductivity | 46.1 W m-1 K-1 |
| Thermal Expansion | 29.9 μm m-1 K-1 |
| Hardness |
|
| Brinell hardness | 26.4 MPa |
| Mohs hardness | 1.2 |
| Elastic Properties |
|
| Bulk modulus | 43 GPa |
| Poisson ratio | 0.45 |
| Shear modulus | 2.8 GPa |
| Young's modulus | 8 GPa |
| Electrical Properties |
|
| Electrical resistivity | 1.5 x 10-7 Ω m |
| Electrical conductivity | 0.0617 106/cm Ω |
| Chemical Properties |
|
| Electrochemical Equivalent | 7.625 g Ah-1 |
| Electron Work Function | 3.84 eV |
| Valence Electron Potential (-eV) | 9.6 |
| Ionization Potential | |
 First
|
6.108 |
| Second
|
20.428 |
| Third
|
29.829 |
| Energy Levels |
|
| Kα1 (intensity 100) |
72.8715 KeV |
| Kα2 (intensity 50) |
70.8319 KeV |
| Kβ1 (intensity 0) |
82.576 KeV |
| Lα1 (intensity 100) |
10.2685 KeV |
| Lα2 (intensity 10) |
10.1728 KeV |
| Lβ1 (intensity 36) |
12.2133 KeV |
| Lβ2 (intensity 20) |
12.2715 KeV |
| Lβ3 (intensity 6.3) |
12.3875 KeV |
| Lβ4 (intensity 4) |
11.9297 KeV |
| Lγ1 (intensity 6) |
14.2915 KeV |
| Lγ2 (intensity 2.7) |
14.62 KeV |
| Lγ3 (intensity 2) |
10.99 KeV |
| Ll (intensity 4.5) |
8.9523 KeV |
| Atomic Radii |
|
| Empirical
|
190 pm |
| Bohr Radius
|
156 pm |
| Covalent Radius
|
148 pm |
| Van der Waals
|
196 pm |
| Triple covalent
|
150 pm |
| Metallic
|
170 pm |
| Oxidation States |
|
| Main
|
Tl+1 |
| Other
|
Tl+3 |
Ionisation Energies (kJ mol-1)  |
|
| M - M+ |
589.3 |
| M+ - M2+ |
1971 |
| M2+ - M3+ |
2878 |
| M3+ - M4+ |
4900 |
| M4+ - M5+ |
6100 |
| M5+ - M6+ |
8300 |
| M6+ - M7+ |
9500 |
| M7+ - M8+ |
11300 |
| M8+ - M9+ |
1400 |
| M9+ - M10+ |
16000 |
| Covalent Bonds (kJ mol-1) |
|
| Tl+1-H
|
185 |
| Tl+3-C
|
125 |
| Tl+3-O
|
375 |
| Tl+3-F
|
460 |
| Tl+3-Cl
|
368 |
| Tl-Tl
|
63 |
| Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 882 | 977 | 1097 | 1252 | 1461 | 1758 |
| Crystal Structure |
|
| Structure
|
Hexagonal close packed |
 |
a = 345.66 pm |
| b = 345.66 pm | |
| c = 552.48 pm | |
| α = 90° | |
| β = 90° | |
| γ = 120° | |