Worked example 5.1 Metallic radii
Use values of rmetal in Table 5.2 to deduce an appropriate
value for the metallic radius (a) rK in metallic K at 298K
and 1 bar pressure, and (b) rSn in a-Sn. Is the answer for part
(b) consistent with the observed interatomic distance in a-Sn of
280 pm?
The values
on going from the first to second row element, but there is
little change on going from the second to third row metal.
This latter observation is due to the presence of a filled 4f
level, and the so-called lanthanoid contraction (see Sections
22.3 and 24.3).