Science / Chemistry / Lanthanide Contraction: An effect that causes sixth period elements with filled 4f subshells to be smaller than otherwise expected. The intervention of the lanthanides increases the effective nuclear charge, which offsets the size increase expected from filling the n=6 valence shell. As a consequence, sixth period transition metals are about the same size as their fifth period counterparts.
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Science / Chemistry / Lanthanide Contraction: An effect that causes sixth period elements with filled 4f subshells to be smaller than otherwise expected. The intervention of the lanthanides increases the effective nuclear charge, which offsets th MORE
Health / Fitness / Peak Contraction: Exercising a muscle until it cramps by using shortened movements. MORE
Science / Chemistry / Lanthanide: Elements 57-70 are called lanthanides. Electrons added during the Aufbau construction of lanthanide atoms go into the 4f subshell. MORE