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Lanthanides and Actinides - Coggle Diagram
Lanthanides and Actinides
Lanthanide Chemistry
Break in lanthanides at Gd - Regular filling of 4f, single electron addition to 5d, instead of paired 4f electrons.
Lanthanide +3 Oxidation state is dominant
Decreasing ion size across a period as a result of the increased Z(eff). Increase in charge density as ion size gets smaller.
More acidic solutions found across the period - with higher charge density, the cationic nature of the H+ ions in solutions hydrolyse more readily/easily.
4th electron stabilised by positive metal charge. Hard to remove for (IV) ox state - 6s electron shield as they have 5 radial nodes.
Poor shielding with increasing Z(eff)/nuclear charge. causes contraction of the F orbitals.
Ionic Bonding - Little interaction with ligands.
No quenching of orbital momentum - so spin only formula to calculate magnetic properties cannot be used.
Actinide Chemistry
Early
Have many similarities to the transition metals - do not behave the same as lanthanides due to oxidation state characteristics.
OX. State = varied
Late
Behave similar/same as lanthanides. +3 Oxidation state dominated.
OX. State = +3
Actinide compounds are intensely coloured. Increased interaction with ligands, so stronger vibrionic coupling (f to d) transitions which are allowed.
Form complex ions due to more interactions with the ligands.
Greater relaxation of selection rules for spectroscopy
Cannot use spin-only approximation to calculate magnetic moments because there is an orbital electronic contribution. It is not quenched - means weak bond formation with ligands.
Complicated Spectra produced + magnetism properties.
Allowed 5F and 6d transition spectra.
Relativistic Effects Valid for actinides.