Coordination Compounds Mind Map

Werner's theory states that a metal in a coordination compound shows primary valence, usually ionisable and related to oxidation state, and secondary valence, non-ionisable and equal to the coordination number. The metal and directly attached ligands form the coordination sphere written inside square brackets.

First separate the part inside square brackets from the ions outside. Use only the ligands directly attached to the metal to find coordination number, and use charge balance to find oxidation state.

IUPAC nomenclature of coordination compounds follows a fixed order: name the cation before the anion, name ligands alphabetically before the metal within the coordination entity, and write the oxidation state of the metal in Roman numerals.

Do the charge calculation before naming the metal. The Roman numeral is not the coordination number; it is the oxidation state of the metal.

Isomerism in coordination compounds occurs when compounds have the same overall composition but differ in the arrangement of ligands, ions, donor atoms, or spatial positions around the metal.

Compare the coordination sphere carefully. If the donor atom changes, think linkage. If ions inside and outside exchange, think ionisation. If positions around the same metal change, think geometrical or optical.

Valence Bond Theory explains bonding in coordination compounds by assuming that the central metal ion uses suitable hybrid orbitals to accept electron pairs donated by ligands, producing definite geometries such as octahedral, square planar, or tetrahedral.

For VBT questions, first find oxidation state and d-electron count, then judge ligand strength and possible pairing before assigning hybridisation and magnetic behaviour.

Crystal Field Theory explains coordination compounds by considering electrostatic interaction between metal d orbitals and ligands, causing the five d orbitals to split into sets of different energy in a ligand field.

For colour and magnetism questions, find the metal oxidation state and d configuration first. Then connect d-electron availability, ligand field strength, and splitting pattern to the property asked.