Germanium

Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard-brittle, grayish-white metalloid in the carbon group, chemically similar to its group neighbors silicon and tin.

What the numbers say

At standard temperature and pressure Germanium is a solid, sitting in period 4, group 14 of the p-block.

Its melting point of 1211 K (938 °C) is the 52nd highest of the 110 elements with a measured value — mid-range among the elements.

At 5.323 g/cm³ it is the 61st densest of 96 elements with a quoted density.

Pauling electronegativity is 2.01. Paired with oxygen (3.44) that is a difference of 1.43, which puts the bond polar covalent — oxides here tend to be semiconducting or refractory rather than salt-like.

In the solid state it takes a face-centered cubic structure — FCC packing gives 12 independent slip systems, which is why FCC metals are the ductile, formable ones.

It is reported in 5 oxidation states (-4, 1, 2, 3, 4), which sets how many distinct compounds and phases it can form.

First identified in 1886.

Crystal structure

Check it against computed structures

The structure search queries the Materials Project, OQMD and the Open Materials Database for computed crystal structures containing Ge — with DFT formation energy, hull stability and band gap where the provider publishes them.