1 pm = 1 x 10-12 metre (meter)

100 pm = 1 Ångstrom

1000 pm = 1 nanometre (nm, nanometer)
Neutral radii

The size of neutral atoms depends upon the way in which the measurement is made and the environment. Follow the appropriate hyperlinks for definitions of each radius type.

The problem is its meaning, which is clearly very different in different sources and books. Two values are given here, one is based upon calculations and the other upon observation - follow the appropriate link for further details.

Ionic radii

This table gives some ionic radii. In this table, geometry refers to the arrangment of the ion's nearest neighbours. Size does depend upon geometry and environment. For electronic configurations, where it matters, the values given for octahedral species are low spin unless stated to be high spin. The terms low spin and high spin refer to the electronic configurations of particular geomtries of certain d-block metal ions. Further information is available in inorganic chemistry textbooks, usually at Level 1 or First Year University level. For definitions of ionic radius and further information, follow the hypertext link.

Ion Coordination type Radius / pm
Be(II) 4-coordinate, tetrahedral 41
Be(II) 6-coordinate, octahedral 59
Pauling ionic radii

This table shows Pauling radii for beryllium
Ion Pauling radius / pm
Be(I) 44
Be(II) 31

This section lists some binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and some other compounds of beryllium.

For each compound, a formal oxidation number for beryllium is given, but the usefulness of this number is limited for p-block elements in particular.

Based upon that oxidation number, an electronic configuration is also given but note that for more exotic compounds you should view this as a guide only.

The term hydride is used in a generic sense to indicate compounds of the type MxHy and not necessarily to indicate that any compounds listed behave chemically as hydrides. In compounds of beryllium (where known), the most common oxidation numbers of beryllium are: 2.

Hydrides

The term hydride is used to indicate compounds of the type MxHy and not necessarily to indicate that any compounds listed behave as hydrides chemically.

Beryllium dihydride: BeH2

Fluorides

Beryllium difluoride: BeF2
Chlorides

Beryllium dichloride: BeCl2