| Ordnungszahl: |
85 |
| Name: |
Astatine |
| Namensursprung: |
Greek: astatos (unstable). |
| Entdeckung: |
1940 by D.R.Corson, K.R.MacKenzie, E.Segré in United States |
| Beschreibung: |
Unstable, radioactive member of the halogen group. |
| Vorkommen: |
Does not occur in nature. Similar to iodine. Produced by bombarding bismuth with alpha particles. |
| Verwendung: |
Since its isotopes have such short half-lives there are no commercially significant compounds of astatine. |
| Gruppe: |
Halogen |
| Atomgewicht: |
(209.9871) |
| Schmelzpunkt: |
302°C |
| Siedepunkt: |
337°C |
| Dichte bei 293 K: |
-- |
| Aggregatszustand bei Raumtemperatur: |
Solid |
| Schalen: |
2,8,18,32,18,7 |
| Orbitale: |
[Xe] 4f14 5d10 6s2 6p5 |
| Valenzen: |
1,3,5,7 |
| 1. Ionisierungs- potential: |
9.5 V |
| 2. Ionisierungs- potential: |
-- |
| 3. Ionisierungs- potential: |
-- |
| Atomradius: |
1.43 Å |
| Spezifische Wärme: |
-- |
| Verdampfungswärme: |
-- |
| Schmelzwärme: |
-- |
| Thermischer Ausdehnungskoeffizient: |
-- |
| Röntgenemission Energie / Wellenlänge: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| eV |
0 |
0 |
11427.2 |
13876.5 |
0 |
0 |
|
|
|
| Å |
0 |
0 |
1.085 |
0.89349 |
0 |
0 |
|
|
|
|
| Röntgenabsorption Energie / Wellenlänge: |
| |
K |
L-I |
L-II |
L-III |
M-I |
M-II |
M-III |
M-IV |
M-V |
| eV |
95724 |
17492 |
16784 |
14213 |
4317 |
4008 |
3426 |
2909 |
2787 |
| Å |
0.12952 |
0.70881 |
0.73871 |
0.87233 |
2.87203 |
3.09345 |
3.61896 |
4.26213 |
4.4487 |
|
| Röntgen Fluoreszenz Ausbeute: |
| |
KA |
KB |
LA |
LB |
MA |
MB |
|
|
|
| |
97.1% |
0% |
41.5% |
0% |
0% |
0% |
|
|
|
|
| Nuklide: |
| |
Anteil |
Gewicht |
Spin |
Halbwertszeit |
Zerfallsmodus |
| At206 |
0% |
206 |
5 |
29.4m |
EC,β+,α |
| At208 |
0% |
208 |
6 |
1.63h |
EC,β+,α |
| At211 |
0% |
210.988 |
9/2 |
7.21h |
EC,α |
| At215 |
0% |
214.999 |
9/2 |
0.10ms |
α |
| At217 |
0% |
217.005 |
9/2 |
32ms |
α,β- |
| At218 |
0% |
218.009 |
0 |
1.6s |
α |
| At219 |
0% |
219.011 |
0 |
50s |
α,β- |
|
