STABILITY, BONDING AND REACTION MECHANISM OF INORGANIC COMPLEXES

Paper Code: 
CHY 121
Credits: 
4
Contact Hours: 
60.00
Max. Marks: 
100.00
Objective: 

Course Objective(s):

This course will enable the students to -

explain the various methods of determination of stability constants, kinetics and reaction mechanism of transition metal complexes and nature of metal-ligand bonding in coordination compounds on the basis of Molecular Orbital Theory.

 

 Course Outcomes (COs):

Course Outcomes

Teaching Learning Strategies

Assessment Strategies

On completion of this course, the students will be able to-

CO1:determine the stability constants of complexes by various methods and predict kinetics and mechanism of ligand substitution reactions in octahedral and square planer complexes

CO2:apply the concept of trans effect to identify and synthesize cis and trans isomers of square planar complexes

CO3:discuss the inner sphere and outer sphere reaction mechanisms

CO4:construct molecular orbital diagrams depicting σ- and π-bonding of complexes using the fundamental knowledge of quantum mechanics

CO5:explain basic principles of angular overlap model and types of bonding in octahedral complexes.

  • Interactive lectures
  • Tutorials
  • Group discussions
  • Use of models
  • Digital learning
  • Problem solving sessions
  • Assertion and Reasoning

 

  • Oral and written examinations
  • Assignments
  • Quiz

 

 

 

 

11.00
Unit I: 
Stability of Complex Ions in Solution

Thermodynamic and kinetic stability, stepwise and overall formation constants, factors affecting stability of complexes, determination of the stability constants of complexes by pH-metric method, ion exchange method, spectrophotometric method and polarographic method, determination of the composition of complexes by Job’s method (method of continuous variation), mole ratio method, slope-ratio method.

13.00
Unit II: 
Mechanism of Reactions of Transition Metal Complexes-I

Kinetics of substitution reactions in octahedral complexes, acid hydrolysis (SN1 mechanism), factors affecting acid hydrolysis and base hydrolysis, conjugate base mechanism (SN1cB mechanism), direct and indirect evidence in favour of conjugate mechanism, anation reactions, reactions without metal ligand bond cleavage, Berry pseudorotation.
Self-Study-Ligand Substitution Reactions-patterns of reactivity, classification of mechanisms- associative, dissociative and interchange mechanism of substitution, energy profile of reaction transition states, inert and labile complexes.


 

12.00
Unit III: 
Mechanism of Reactions of Transition Metal Complexes-II

Trans effect, theories of trans effect and its uses, mechanism of substitution in square planar complexes, factors affecting substitution reactions in square planar complexes, Swain Scott equation, cis-trans isomerization.
Redox Reactions- classification, mechanism of one electron transfer reaction- outer sphere type reactions, cross reactions and Marcus-Hush theory (qualitative treatment), inner sphere type reactions, two electron transfer reaction (brief idea).

12.00
Unit IV: 
Molecular Orbital Theory-I (σ-bonding)

Ligand Field Theory- an introduction, molecular orbital diagrams of some simple polyatomic molecules like BeH2, H2O, NH3, Walsh diagrams.
LCAO approximation, σ-only molecular orbital energy levels for octahedral, tetrahedral and square planar complexes.

 

12.00
Unit V: 
Molecular Orbital Theory-II (π-bonding)

Molecular orbital energy levels for octahedral, tetrahedral and square planar complexes containing π-bonds, effect of π-bonding. Experimental evidence for π-bonding- crystallography and infra-red spectroscopy.
Angular Overlap Model- principle, σ- and π- bonding in octahedral complexes.

Essential Readings: 
  • Principles of Inorganic Chemistry, Thirty Third Edition; B.R. Puri, L.R. Sharma, K.C. Kalia; Vishal Publishing Co., Delhi, 2020.
  • Inorganic Chemistry (Principle of Structure and Reactivity), Fourth Edition; J. E Huheey, E. A. Keiter, R. L. Keiter; Pearson India, New Delhi, 2013.

 

References: 
Academic Year: