Explore optical isomerism, linkage isomerism, and ionisation isomerism in coordination compounds. Includes practice questions to test your understanding.
[Cr(en)2(H₂O)2]3+ is octahedral with 2 en (bidentate) and 2 H₂O (unidentate). The 2 en ligands create the propeller-like structure causing chirality.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
SCN− is ambidentate, binding via S (thiocyanato) or N (isothiocyanato), allowing linkage isomerism when replaced or reoriented.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
Linkage isomerism occurs with ambidentate ligands like NO₂−, which can bind via N or O. [Co(NH₃)5NO₂]2+ can form [Co(NH₃)5ONO]2+, showing linkage isomerism.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
Optical isomerism occurs in chiral complexes. [Co(en)3]3+ (octahedral, with 3 bidentate en ligands) lacks a plane of symmetry, forming non-superimposable mirror images (d and l).
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Co(en)2(H₂O)Cl]2+ (octahedral) with 2 bidentate en, 1 H₂O, and 1 Cl− forms a chiral complex without symmetry.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Cr(NH₃)6][Co(CN)6] swaps NH₃ and CN− between Co and Cr, showing coordination isomerism.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Fe(en)2Cl₂]+ (octahedral) with 2 bidentate en and 2 Cl− can form a cis isomer that is chiral, lacking symmetry.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
A heteroleptic complex has different types of ligands. [Co(NH₃)5Cl]2+ has NH₃ and Cl−, unlike [Co(NH₃)6]3+ (homoleptic).
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Co(CN)6]3− (Co₃+, d6) with strong field CN− is low spin (t2g6), with 0 unpaired electrons.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Cr(H₂O)3Cl₃] (octahedral, [Ma₃b3]) can have a facial (fac) isomer where 3 Cl− ligands occupy one face.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
SCN− is ambidentate (S or N binding), while CN− binds only via C. Thus, SCN− can form linkage isomers.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
[Co(en)2Cl₂]+ (octahedral) can form a trans isomer (symmetric) and a cis isomer (chiral, non-superimposable), showing optical isomerism.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
