Properties | More Info | Isotopes | Spectra
Compounds | Reactions | Production
Atomic: M.A.C. | Reference
Images | Video
Praseodymium
Electron Configuration 2,8,18,21,8,2
Electron Configuration [Xe] 4f3 6s2
Ground state 49/2
Atomic Volume 20.8 g/cm3
Electronegativity 1.13
Magnetic ordering No data
Mass magnetic susceptibility 4.23 x 10-7
Molar magnetic susceptibility 5.9604 x 10-8
Speed of sound 2280 m s-1
Thermal Properties
Enthalpy of Atomization 368 kJ mol-1 @25°C
Enthalpy of Fusion 11.3 kJ mol-1
Enthalpy of Vaporisation 357 kJ mol-1
Heat Capacity 27.20 J mol-1 K-1
Thermal Conductivity 12.5 W m-1 K-1
Thermal Expansion 6.7 μm m-1 K-1
Hardness
Brinell hardness 481 MPa
Vickers hardness 400 MPa
Elastic Properties
Bulk modulus 28.8 GPa
Poisson ratio 0.281
Shear modulus 14.8 GPa
Young's modulus 37.3 GPa
Electrical Properties
Electrical resistivity 7.0 x 10-7 Ω m
Electrical conductivity No data.
Chemical Properties
Electrochemical Equivalent 1.7524 g Ah-1
Electron Work Function 2.7 eV
Valence Electron Potential (-eV) 42.64
Ionization Potential  
First 5.46
Second 10.551
Third 21.62
Energy Levels
Kα1 (intensity 100) 36.0263 KeV
Kα2 (intensity 50) 35.5502 KeV
Kβ1 (intensity 21.6) 40.7482 KeV
Kβ2 (intensity 7.1) 41.7557 KeV
Kβ3 (intensity 9.1) 40.6435 KeV
Lα1 (intensity 100) 5.0337 KeV
Lα2 (intensity 10) 5.0135 KeV
Lβ1 (intensity 52) 5.4889 KeV
Lβ2 (intensity 22) 5.85 KeV
Lβ3 (intensity 12) 5.5943 KeV
Lβ4 (intensity 4) 5.4977 KeV
Lγ1 (intensity 5.5) 6.3221 KeV
Lγ2 (intensity 1.5) 6.5998 KeV
Lγ3 (intensity 2) 4.934 KeV
Ll (intensity 3.5) 4.4614 KeV
Atomic Radii
Empirical 185 pm
Bohr Radius 247 pm
Covalent Radius No data.
Van der Waals No data.
Triple covalent 128 pm
Metallic 182.4 pm
Ionic Radii (Å)
Charge Coordination Crystal Ionic Key
VI 1.13 0.99 R
VIII 1.266 1.126 R
IX 1.319 1.179 R
VI 0.99 0.85 R
VIII 1.1 0.96 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
Main Pr+3
Other Pr+4
Ionisation Energies (kJ mol-1) show graph
M - M+ 523.1
M+ - M2+ 1018
M2+ - M3+ 2086
M3+ - M4+ 3761
M4+ - M5+ 5543
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
T (K) 1771 1973 (2227) (2571) (3054) (3779)
Crystal Structure
Structure Hexagonal close packed
a = 367.25 pm
b = 367.25 pm
c = 1183.54 pm
α = 90°
β = 90°
γ = 120°