Ordnungszahl: |
95 |
Name: |
Americium |
Namensursprung: |
Named for the American continent, by analogy with europium. |
Entdeckung: |
1945 by G.T.Seaborg, R.A.James, L.O.Morgan, A.Ghiorso in United States |
Beschreibung: |
Silvery-white, artificially produced radioactive metal. |
Vorkommen: |
Produced by bombarding plutonium with neutrons. |
Verwendung: |
Americium-241 is currently used in smoke detectors. |
Gruppe: |
Transition Metal |
Atomgewicht: |
(243.0614) |
Schmelzpunkt: |
994°C |
Siedepunkt: |
2607°C |
Dichte bei 293 K: |
13.6 g/cm³ |
Aggregatszustand bei Raumtemperatur: |
Solid |
Schalen: |
2,8,18,32,25,8,2 |
Orbitale: |
[Rn] 5f7 7s2 |
Valenzen: |
2,3,4,5,6 |
1. Ionisierungs- potential: |
5.993 V |
2. Ionisierungs- potential: |
-- |
3. Ionisierungs- potential: |
-- |
Atomradius: |
-- |
Spezifische Wärme: |
0.11 J/gK |
Verdampfungswärme: |
-- |
Schmelzwärme: |
14.40 kJ/mol |
Thermischer Ausdehnungskoeffizient: |
7.1 10-6 K-1 |
Röntgenemission Energie / Wellenlänge: |
|
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
eV |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
|
Å |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
|
|
Röntgenabsorption Energie / Wellenlänge: |
|
K |
L-I |
L-II |
L-III |
M-I |
M-II |
M-III |
M-IV |
M-V |
eV |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
Å |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
Röntgen Fluoreszenz Ausbeute: |
|
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
|
0% |
0% |
0% |
0% |
0% |
0% |
|
|
|
|
Nuklide: |
|
Anteil |
Gewicht |
Spin |
Halbwertszeit |
Zerfallsmodus |
Am240 |
0% |
240 |
3/2 |
2.12d |
EC,α |
Am241 |
0% |
241.057 |
5/2 |
432.7y |
α |
Am242 |
0% |
242 |
1 |
16.02h |
β-,EC |
Am242m |
0% |
242 |
5 |
141y |
IT,α |
Am243 |
0% |
243.061 |
5/2 |
7.37E03y |
α |
Am244 |
0% |
244 |
6 |
10.1h |
β- |
Am245 |
0% |
245 |
5/2 |
2.05h |
β- |
Am246 |
0% |
246 |
7/2 |
39m |
β- | |