Meitnerium (Mt)

Meitnerium is a chemical element with symbol Mt and atomic number 109. It is named after physicist Lise Meitner. As a synthetic element, it can be created in a laboratory but is not found in nature.

Atomic Number

109

Atomic Mass

278 u

Phase

Predicted solid

Density

~37.4 (predicted) g/cm³

Electron Shells

2, 8, 18, 32, 32, 15, 2

Atomic Structure

Protons: 109 • Electrons: 109 • Neutrons: Varies by isotope

Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d⁷

Discovery

1982 • Peter Armbruster, Gottfried Munzenberg