プロメチウム

61
Pm
該当なし
周期
6
ブロック
f
陽子
電子
中性子
61
61
84
一般特性
原子番号
61
原子量
[145]
質量数
145
カテゴリ
ランタノイド
銀色
放射性
はい
Named after the Greek Prometheus, who, according to mythology, stole fire from heaven
結晶構造
該当なし
歴史
The existence of an element between neodymium and samarium was first predicted by Czech chemist Bohuslav Brauner in 1902.

Promethium was first produced and characterized at Oak Ridge National Laboratory in 1945 by Jacob A. Marinsky, Lawrence E. Glendenin and Charles D. Coryell.

It was produced by the separation and analysis of the fission products of uranium fuel irradiated in a graphite reactor.
電子殻
2, 8, 18, 23, 8, 2
電子配置
[Xe] 4f5 6s2
Pm
Promethium is the only lanthanide that has no stable isotopes
物理特性
固体
密度
7.26 g/㎝3
融点
1315.15 K | 1042 °C | 1907.6 °F
沸点
3273.15 K | 3000 °C | 5432 °F
融解熱
7.7 kJ/mol
蒸発熱
290 kJ/mol
熱容量
-
地殻中における存在比
該当なし
宇宙空間における存在比
該当なし
Pitchblende,
画像の出典: Wikimedia Commons (Geomartin)
Pitchblende, a uranium ore and the host for most of Earth's promethium
CAS登録番号
7440-12-2
PubChem CID番号
該当なし
原子特性
原子半径
183 pm
共有結合半径
199 pm
電気陰性度
-
イオン化エネルギー
5.582 eV
モル体積
22.39 ㎝3/mol
熱伝導率
0.179 W/㎝·K
酸化数
3
用途
Promethium is also used in atomic batteries for spacecraft and guided missiles.

Promethium is also used to measure the thickness of materials by evaluating the amount of radiation from a promethium source that passes through the sample.

It has possible future uses in portable X-ray sources, and as auxiliary heat or power sources for space probes and satellites.
Promethium is harmful due to its radioactivity
同位体
安定同位体
-
不安定同位体
126Pm, 127Pm, 128Pm, 129Pm, 130Pm, 131Pm, 132Pm, 133Pm, 134Pm, 135Pm, 136Pm, 137Pm, 138Pm, 139Pm, 140Pm, 141Pm, 142Pm, 143Pm, 144Pm, 145Pm, 146Pm, 147Pm, 148Pm, 149Pm, 150Pm, 151Pm, 152Pm, 153Pm, 154Pm, 155Pm, 156Pm, 157Pm, 158Pm, 159Pm, 160Pm, 161Pm, 162Pm, 163Pm