|
|
Pronunciation | (NEE-oh-DIM-ee-əm) |
---|
Appearance | silvery white |
---|
|
|
| 144.242(3)[1] |
---|
|
|
|
Atomic number (Z) | 60 |
---|
Group | f-block groups (no number) |
---|
Period | period 6 |
---|
Block | f-block |
---|
Electron configuration | [Xe] 4f4 6s2 |
---|
Electrons per shell | 2, 8, 18, 22, 8, 2 |
---|
|
Phase at STP | solid |
---|
Melting point | 1297 K (1024 °C, 1875 °F) |
---|
Boiling point | 3347 K (3074 °C, 5565 °F) |
---|
Density (near r.t.) | 7.01 g/cm3 |
---|
when liquid (at m.p.) | 6.89 g/cm3 |
---|
Heat of fusion | 7.14 kJ/mol |
---|
Heat of vaporization | 289 kJ/mol |
---|
Molar heat capacity | 27.45 J/(mol·K) |
---|
Vapor pressure
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
1595 |
1774 |
1998 |
(2296) |
(2715) |
(3336) |
|
|
Oxidation states | 0,[2] +2, +3, +4 (a mildly basic oxide) |
---|
Electronegativity | Pauling scale: 1.14 |
---|
Ionization energies | - 1st: 533.1 kJ/mol
- 2nd: 1040 kJ/mol
- 3rd: 2130 kJ/mol
-
|
---|
Atomic radius | empirical: 181 pm |
---|
Covalent radius | 201±6 pm |
---|
Spectral lines of neodymium |
|
Natural occurrence | primordial |
---|
Crystal structure | double hexagonal close-packed (dhcp) |
---|
Speed of sound thin rod | 2330 m/s (at 20 °C) |
---|
Thermal expansion | α, poly: 9.6 µm/(m⋅K) (at r.t.) |
---|
Thermal conductivity | 16.5 W/(m⋅K) |
---|
Electrical resistivity | α, poly: 643 nΩ⋅m |
---|
Magnetic ordering | paramagnetic, antiferromagnetic below 20 K[3] |
---|
Molar magnetic susceptibility | +5628.0×10−6 cm3/mol (287.7 K)[4] |
---|
Young's modulus | α form: 41.4 GPa |
---|
Shear modulus | α form: 16.3 GPa |
---|
Bulk modulus | α form: 31.8 GPa |
---|
Poisson ratio | α form: 0.281 |
---|
Vickers hardness | 345–745 MPa |
---|
Brinell hardness | 265–700 MPa |
---|
CAS Number | 7440-00-8 |
---|
|
Discovery | Carl Gustaf Mosander (1841) |
---|
First isolation | Carl Auer von Welsbach (1885) |
---|
Named by | Carl Auer von Welsbach (1885) |
---|
|
|
Main isotopes[5] |
Decay |
|
abundance |
half-life (t1/2) |
mode |
product |
142Nd |
27.2% |
stable |
143Nd |
12.2% |
stable |
144Nd |
23.8% |
2.29×1015 y |
α |
140Ce |
145Nd |
8.3% |
stable |
146Nd |
17.2% |
stable |
148Nd |
5.80% |
stable |
150Nd |
5.60% |
6.7×1018 y |
β−β− |
150Sm |
|
|
Category: Neodymium | references |