f- and d- Block Elements ## Topic: Trends in the periodic properties of f- and d- block elements

Atomic and ionic radii:

• General trend: decrease across a period and increase down a group
• Lanthanide contraction: gradual decrease in atomic and ionic radii of lanthanides due to poor shielding effect of 4f electrons
• Actinide contraction: similar to lanthanide contraction, but less pronounced

Ionization energy:

• General trend: increase across a period and decrease down a group
• Exception: irregularities in the ionization energies of some transition metals due to the stability of half-filled and fully-filled d orbitals

Electron affinity:

• General trend: increase across a period and decrease down a group
• Lanthanides and actinides have low electron affinities due to their large size and diffuse orbitals

Oxidation states:

• Transition metals exhibit multiple oxidation states due to the presence of multiple d electrons
• Lanthanides and actinides generally have +3 oxidation state due to the stability of their half-filled or fully-filled f orbitals

Magnetic properties:

• Paramagnetism: presence of unpaired electrons in the d or f orbitals
• Diamagnetism: absence of unpaired electrons

Catalytic properties:

• Transition metals and their compounds are widely used as catalysts due to their ability to form coordination complexes and activate reactants

Topic: General characteristics of the lanthanides and actinides

Electronic configuration:

• Lanthanides: [Xe]4f^1-145d^06s^2
• Actinides: [Rn]5f^1-145d^0-106s^2

Oxidation states:

• Lanthanides: +3
• Actinides: +3, +4, +5, +6

Colour:

• Lanthanides: colourless or pale-coloured due to the shielding effect of 4f electrons
• Actinides: mostly coloured due to the presence of unpaired f electrons

Magnetic properties:

• Lanthanides: paramagnetic due to the presence of unpaired f electrons
• Actinides: paramagnetic or ferromagnetic due to the presence of unpaired f electrons

Complexation behaviour:

• Lanthanides and actinides form coordination complexes with various ligands, including water, halide ions, and organic molecules

Lanthanide contraction:

• Gradual decrease in atomic and ionic radii of lanthanides due to poor shielding effect of 4f electrons
• Consequences:
• Close packing of lanthanide ions in crystals
• Increase in the basicity and stability of lanthanide hydroxides and carbonates

Topic: Chemistry of the lanthanides

Preparation of lanthanide compounds:

• Reduction of lanthanide halides with alkali metals or calcium
• Thermal decomposition of lanthanide carbonates or oxalates

Properties and reactions of lanthanide compounds:

• Lanthanide compounds are generally ionic in nature
• Lanthanide ions are Lewis acids and form coordination complexes with various ligands
• Lanthanide compounds are generally stable to oxidation and reduction
• Lanthanide hydroxides and carbonates are basic and insoluble in water

Applications of lanthanide compounds:

• Lanthanide compounds are used in:
• Phosphors for lighting and display screens
• Magnets
• Lasers
• Catalysts
• Polishing agents
• X-ray contrast agents

Topic: Chemistry of the actinides

Preparation of actinide compounds:

• Reduction of actinide halides with alkali metals or calcium
• Precipitation of actinide hydroxides or carbonates from actinide solutions

Properties and reactions of actinide compounds:

• Actinide compounds are generally ionic in nature
• Actinide ions are Lewis acids and form coordination complexes with various ligands
• Actinide compounds are generally unstable to oxidation and reduction
• Actinide hydroxides and carbonates are basic and insoluble in water

Applications of actinide compounds:

• Actinide compounds are used in:
• Nuclear reactors as fuel and targets
• Radioactive tracers
• Medical imaging and therapy
• Smoke detectors
• Neutron sources

Topic: Coordination complexes of f- and d- block elements

Types of ligands:

• Ligands are molecules or ions that donate electron pairs to metal ions
• Common types of ligands include:
• Anions (e.g., Cl^-, Br^-, I^-)
• Neutral molecules (e.g., H2O, NH3, CO)
• Organic molecules (e.g., EDTA, acetylacetone)

Bonding in coordination complexes:

• Coordination complexes are formed by the interaction between metal ions and ligands
• The bonding in coordination complexes can be explained by:
• Ionic bonding
• Covalent bonding
• Coordinate covalent bonding

Stability of coordination complexes:

• The stability of coordination complexes is influenced by various factors, including:
• The charge of the metal ion
• The size of the metal ion
• The electronegativity of the ligand
• The number of donor atoms in the ligand

Isomerism in coordination complexes:

• Isomerism is the phenomenon of compounds having the same molecular formula but different structures
• Different types of isomerism in coordination complexes include:
• Structural isomerism
• Stereoisomerism

Applications of coordination complexes:

• Coordination complexes have wide-ranging applications including:
• Catalysts
• Pigments
• Medicines
• Analytical reagents
• Magnetic materials

Topic: Organometallic compounds of f- and d- block elements

Types of organometallic compounds:

• Organometallic compounds are compounds that contain metal-carbon bonds
• Different types of organometallic compounds include:
• Metal alkyls
• Metal aryls
• Metal carbonyls
• Metallocenes

Bonding in organometallic compounds:

• The bonding in organometallic compounds can be explained by:
• Ionic bonding
• Covalent bonding
• Coordinate covalent bonding

Reactions of organometallic compounds:

• Organometallic compounds undergo various reactions, including:
• Substitution reactions
• Addition reactions
• Elimination reactions
• Redox reactions

Applications of organometallic compounds:

• Organometallic compounds have various applications, including:
• Catalysts
• Pharmaceuticals
• Fuel additives
• Plastic additives
• Pesticides

Topic: Bioinorganic chemistry of f- and d- block elements

Role of metal ions in biological systems:

• Metal ions play crucial roles in biological systems, including:
• Structural functions
• Catalytic functions
• Transport functions
• Signal transduction
• Electron transfer

Metalloenzymes:

• Metalloenzymes are enzymes that contain metal ions as cofactors
• Examples of metalloenzymes include:
• Cytochrome oxidase (Cu, Fe)
• Nitrogenase (Mo, Fe)
• Carbonic anhydrase (Zn)

Metal complexes in medicine:

• Metal complexes have various applications in medicine, including:
• Cisplatin (Pt) for cancer treatment
• Iron-dextran for iron deficiency
• Gadolinium contrast agents for MRI

Topic: Industrial applications of f- and d- block elements

Metallurgy:

• Metallurgy involves the extraction and purification of metals from their ores
• f- and d- block elements are used in various metallurgical processes, including:
• Smelting
• Refining
• Alloying

Ceramics:

• Ceramics are inorganic, non-metallic materials that are fired at high temperatures
• f- and d- block elements are used in the production of various ceramic materials, including:
• Porcelain
• Glass
• Cement
• Bricks

Glass:

• Glass is a transparent, amorphous solid made by melting sand (SiO2) with other materials
• f- and d- block elements are used in the production of various types of glass, including:
• Float glass
• Borosilicate glass
• Safety glass

Pigments:

• Pigments are colouring agents that are used in paints, inks, and other materials
• f- and d- block elements are used in the production of various pigments, including:
• Titanium dioxide (TiO2)
• Iron oxide (Fe2O3)
• Chromium oxide (Cr2O3)

Catalysts:

• Catalysts are substances that increase the rate of a chemical reaction without being consumed in the reaction
• f- and d- block elements are used in the production of various catalysts, including:
• Platinum (Pt) for catalytic converters
• Palladium (Pd) for hydrogenation reactions
• Rhodium (Rh) for hydroformylation reactions

Magnets:

• Magnets are materials that attract or repel each other due to the presence of magnetic fields
• f- and d- block elements are used in the production of various magnetic materials, including:
• Iron (Fe)
• Cobalt (Co)
• Nickel (Ni)

Superconductors:

• Superconductors are materials that conduct electricity with zero resistance at very low temperatures
• f- and d- block elements are used in the production of various superconductors, including:
• Niobium (Nb)
• Tantalum (Ta)
• Lead (Pb) Some useful links:
• [f-block elements](https://chem.libretexts.org/Courses/John_Jay_College_of_Criminal_