Gadolinium

64
Gd
Gruppe
n/a
Periode
6
Block
f
Protonen
Elektronen
Neutronen
64
64
93
Generelle Eigenschaften
Ordnungszahl
64
Atommasse
157,25
Massenzahl
157
Kategorie
Lanthanoide
Farbe
Silber
Radioaktiv
Nein
From gadolinite, a mineral named for Gadolin, a Finnish chemist
Kristallstruktur
Einfach hexagonal
Geschichte
Gadolinium was first detected spectroscopically in 1880 by the Swiss chemist Jean Charles Galissard de Marignac who separated its oxide.

He observed spectroscopic lines due to gadolinium in samples of gadolinite and in the separate mineral cerite.

The metal was isolated by Paul Emile Lecoq de Boisbaudran in 1886.
Elektronen pro Schale
2, 8, 18, 25, 9, 2
Elektronenkonfiguration
[Xe] 4f7 5d1 6s2
Gd
Gadolinium has the highest neutron cross-section among any stable nuclides
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
7,895 g/cm3
Schmelzpunkt
1585,15 K | 1312 °C | 2393,6 °F
Siedepunkt
3546,15 K | 3273 °C | 5923,4 °F
Schmelzwärme
10 kJ/mol
Verdampfungswärme
305 kJ/mol
Spezifische Wärmekapazität
0,236 J/g·K
Häufigkeit in der Erdkruste
0,00052%
Häufigkeit im Universum
2×10-7%
Ultrapure
Danksagungen für Bilder: Images-of-elements
Ultrapure amorphous gadolinium
CAS-Nummer
7440-54-2
PubChem CID-Nummer
23982
Atomeigenschaften
Atomradius
180 pm
Kovalenter Radius
196 pm
Elektronegativität
1,2 (Pauling-Skala)
Ionisierungsenergie
6,1501 eV
Molares Volumen
19,9 cm3/mol
Wärmeleitfähigkeit
0,106 W/cm·K
Oxidationszustände
1, 2, 3
Anwendung
Gadolinium is used to make gadolinium yttrium garnets which have microwave applications.

It is also used in intravenous radiocontrast agents in magnetic resonance imaging (MRI).

Gadolinium compounds are used for making green phosphors for color TV tubes, and in manufacturing compact discs.
Gadolinium is considered to be moderately toxic
Isotope
Stabile Isotope
154Gd, 155Gd, 156Gd, 157Gd, 158Gd, 160Gd
Instabile Isotope
134Gd, 135Gd, 136Gd, 137Gd, 138Gd, 139Gd, 140Gd, 141Gd, 142Gd, 143Gd, 144Gd, 145Gd, 146Gd, 147Gd, 148Gd, 149Gd, 150Gd, 151Gd, 152Gd, 153Gd, 159Gd, 161Gd, 162Gd, 163Gd, 164Gd, 165Gd, 166Gd, 167Gd, 168Gd, 169Gd