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Atomic: M.A.C. | Reference
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Neodymium
Electron Configuration 2,8,18,22,8,2
Electron Configuration [Xe] 4f4 6s2
Ground state 5I4
Atomic Volume 20.6 g/cm3
Electronegativity 1.14
Magnetic ordering Ferromagnetic
Mass magnetic susceptibility 4.8 x 10-7
Molar magnetic susceptibility 6.9235 x 10-8
Speed of sound 2330 m s-1
Thermal Properties
Enthalpy of Atomization 322 kJ mol-1 @25°C
Enthalpy of Fusion 7.11 kJ mol-1
Enthalpy of Vaporisation 328 kJ mol-1
Heat Capacity 27.45 J mol-1 K-1
Thermal Conductivity 16.5 W m-1 K-1
Thermal Expansion 9.6 μm m-1 K-1
Hardness
Brinell hardness 265 MPa
Vickers hardness 343 MPa
Elastic Properties
Bulk modulus 31.8 GPa
Poisson ratio 0.281
Shear modulus 16.3 GPa
Young's modulus 41.4 GPa
Electrical Properties
Electrical resistivity 6.4 x 10-7 Ω m
Electrical conductivity No data.
Chemical Properties
Electrochemical Equivalent 1.7939 g Ah-1
Electron Work Function 3.2 eV
Valence Electron Potential (-eV) 43.4
Ionization Potential  
First 5.53
Second 10.727
Third 22.076
Energy Levels
Kα1 (intensity 100) 37.361 KeV
Kα2 (intensity 50) 36.8474 KeV
Kβ1 (intensity 21.9) 42.2713 KeV
Kβ2 (intensity 7.3) 43.3204 KeV
Kβ3 (intensity 9.1) 42.1568 KeV
Lα1 (intensity 100) 5.2304 KeV
Lα2 (intensity 10) 5.2077 KeV
Lβ1 (intensity 50) 5.7216 KeV
Lβ2 (intensity 20) 6.0894 KeV
Lβ3 (intensity 10) 5.8288 KeV
Lβ4 (intensity 4) 5.7237 KeV
Lγ1 (intensity 5.5) 6.6021 KeV
Lγ2 (intensity 2) 6.8802 KeV
Lγ3 (intensity 2) 5.144 KeV
Ll (intensity 3.5) 4.6355 KeV
Atomic Radii
Empirical 185 pm
Bohr Radius 206 pm
Covalent Radius No data.
Van der Waals No data.
Triple covalent No data.
Metallic 181.4 pm
Ionic Radii (Å)
Charge Coordination Crystal Ionic Key
VIII 1.43 1.29
IX 1.49 1.35
VI 1.123 0.983 R
VIII 1.249 1.109 R*
IX 1.303 1.163 R
XII 1.41 1.27 E
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 Nd+3
Other Nd+2, Nd+4
Ionisation Energies (kJ mol-1) show graph
M - M+ 529.6
M+ - M2+ 1035
M2+ - M3+ 2130
M3+ - M4+ 3899
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
T (K) 1595 1774 1998 (2296) (2715) (3336)
Crystal Structure
Structure Hexagonal close packed
a = 365.8 pm
b = 365.8 pm
c = 1179.9 pm
α = 90°
β = 90°
γ = 120°