Actinide contraction definition in chemistry
The atomic and ionic radii of the actinide elements gradually decreases as we move from thorium to lawrencium along actinide series.
Thus,on
going from Th 3+to Lr 3+
ion ,the ionic radius decrease from
109 pm to 98 pm . There is also a steady
decrease in the radii of An 4+ ion [ An = actinide ] .
This steady
decrease in atomic and ionic radii with increasing atomic number of actinide
elements that is, positive nuclear charge , is called actinide contraction and
it is analogous to lanthanide
contraction.
