61

Radioactive

Pm

Promethium

(145)

Lathanide
Solid

Discovery

Marinsky, J. A. & Glendenin, L. E. (1945)

Etymology

Greek

Meaning

Foretthought

Electron configuration

Electron configuration

Crystal structure

Crystal structure

Double hexagonal close-packed

Physical Properties

Phase

  (at 21 °C and 101.325 kPa)

Solid

Melting point

  (at 101.325 kPa)

1100.0 °C

1373.15 K

Boiling point

  (at 101.325 kPa)

3127.0 °C

3400.15 K

Density

  (at 21 °C and 101.325 kPa)

7.30 g/cm3

Electronegativity

0.00