The actinoid series consists of 15 metallic elements from atomic numbers 89 to 103, starting with actinium and ending with lawrencium. These elements are known for their radioactive properties and are typically found in the f-block of the periodic table.
Lanthanide Series: A group of 15 metallic elements from atomic numbers 57 to 71, starting with lanthanum and ending with lutetium. They have similar properties to the actinoids but are typically less radioactive.
Transition Metals: Elements found in groups 3-12 of the periodic table that have partially filled d electron sub-shells. They often form colored compounds and can have multiple oxidation states.
Coordination Compounds: Complexes formed from a central metal atom bonded to surrounding ligands through coordinate covalent bonds. These compounds exhibit unique chemical behaviors including variable oxidation states and catalytic activities.