Module Details
The information contained in this module specification was correct at the time of publication but may be subject to change, either during the session because of unforeseen circumstances, or following review of the module at the end of the session. Queries about the module should be directed to the member of staff with responsibility for the module.
Title INORGANIC CHEMISTRY FOR MCHEM STUDENTS
Code CHEM214
Coordinator Dr JA Iggo
Chemistry
Year CATS Level Semester CATS Value
Session 2008-09 Level Two Second Semester 15

Aims

Aims:

This module is an introduction to the co-ordination and organometallic chemistry of 3d transition metals, and will encompass theory, physical methods and descriptive chemistry.

The aims of the module are:

  • To outline how bonding theories (valence bond, crystal field, ligand field) have been developed by chemists to rationalise important properties of the d–block elements, many of which distinguish them from organic and main group compounds
  • To illustrate the chemistry of the transition elements by a detailed study of three groups, Ti/Zr/Hf, Fe/Ru/Os and Ni/Pd/Pt, including:
    • Discovery, isolation and technological importance of the elements and their compounds
    • A survey of the chemistry of the different oxidation states and a comparison of the 3d elements with their heavier 4d and 5d relatives
    • Brief comparisons/contrasts with neighbouring groups of elements.
  • To introduce the theory underlying the use of appropriate physical and spectroscopic techniques for characterising d–block complexes, and examples of their application.
  • To introduce the chemistry, and some applications, of complexes in low oxidation states, including:
    • CO as an examplar of a p-acceptor ligand
    • 3d Metal carbonyl complexes
    • Analogous ligands, e.g. NO, RNC
    • The 18-electron rule; what it is, and why it applies to these complexes.

 


Learning Outcomes

By the end of the module students should:

  • Show an understanding of the concepts, applications and limitations of the different bonding theories relevant to transition-metal complex chemistry, and be aware of their relative relevance in different chemical contexts.
  • Be able to identify key elements of the structures of transition-metal complexes, and apply their knowledge of spectroscopic and physical techniques to work out the correct structure for a complex, given relevant chemical and spectroscopic information.
  • Be able to describe the social, economic and technological importance of selected transition elements.
  • Understand and be able to describe the significance of the syntheses, characterisation and chemistry of 3d metal complexes encountered in the practical module, CHEM245.
  • Understand the origin of the18 -electron rule, its application and the sort of complexes to which it applies.

Syllabus
0 

Essential concepts in Transition Metal Chemistry – An Introduction

  • Introduction to transition metal complexes. Coordination complexes and coordinate bonds. Oxidation state. Coordination number. Atomic d orbitals, dn configuration.
  • Ligands, hard and soft donors. Electroneutrality.
  • Geometry, and isomerism.
  • Formation of complexes in solution. Stability constants. The chelate effect.
  • Crystal field theory. The basis of crystal field theory (CFT) for octahedral complexes. The origin of D. Factors affecting size of D. Colours in transition metal complexes; d–d transitions, selection rules. Charge transfer transitions.
  • Magnetic properties. High–spin and low–spin complexes. Magnetic moment, spin–only formula.
  • Crystal field s tabilisation energy (CFSE). Favoured geometries, ionic radii, hydration enthalpies, latticed energies. Kinetic vs thermodynamic stability of complexes. Irving-Williams series.

Further Bonding in Transition Metal Complexes

  • Magnetic properties. Spin–only formula. Distinguishing high– and low–spin cases. Colours in transition metal complexes – how they arise. d–d Transitions. Selection rules. The d1 case.
  • Charge transfer bands. Chemical evidence for CFSE. Its effect on chemistry of some metal ions.
  • The Jahn–Teller effect. How it arises. Its effect on (i) structure, (ii) chemistry, (iii) spectra of complexes. Geometries other than octahedral: 4–coordination.(i) Tetrahedral and (ii) square planar complexes in CFT terms. Factors favouring (i) square planar and (ii) tetrahedra l complexes.
  • Where CFT breaks down. Covalence in metal–ligand bonds. Spectrochemical series revisited. Molecular orbital theory – revision. Its application to complexes. Comparison of MOT and CFT pictures for octahedral complexes. p –Bonding in complexes. High and low oxidation state complexes and their stabilisation by p–donor and p–acceptor ligands.

 

Transition Metal Descriptive Chemistry

  • Transition metal descriptive chemistry: introduction. Trends across the d–block: oxidation state stabilities, with examples. Differences between 3d and 4d/5d elements.
  • The early transition elements: Titanium, zirconium and hafnium chemistry.
  • Mid–transition metals: The chemistry of iron
  • Mid–transition metals: The chemistry of ruthenium and osmium , and comparisons with iron.
  • Late transition elements: The chemistry of nickel.
  • Late transition elements: The chemistry of palladium and platinum, and comparisons with nickel.


Transition Metal Complexes Containing CO and other p-Acceptor Ligands

  • Introduction to non-classical complexes containing p-acid ligands. 18 electron rule, bonding picture and comparison with classical complexes; synergistic bonding.
  • Preparation, structure and bonding, chemical properties, reactivity and uses of:
    • Binary metal carbonyls - preparation, characterisation, physical and chemical properties. Application of physical techniques (X-Ray crystallography, vibrational and NMR spectroscopies) for their characterisation. Bonding modes and electronic structure.
    • Metal carbonyl hydrides
    • Metal carbonyl-anions, -cations and -halides
    • Complexes containing PR3, AsR3 and other p -acceptor ligands - electronic and steric effects, and cone angle concept.
Complexes containing CO analogues -nitric oxide (NO),isonitriles (RNC) and dinitrogen

Teaching and Learning Strategies

The course will be delivered in three blocks of 50-minute lectures, 11 on bonding theories, 11 on 3d metal descriptive chemistry and 11 on low oxidation state chemistry, p-acceptorligands and the 18-electron rule. These will be supported by five one-hour problem-based tutorials. Students will be expected to spend at least eight hours a week on private study related to this module.


Teaching Schedule
  Lectures Seminars Tutorials Lab Practicals Fieldwork Placement Other TOTAL
Study Hours 31

   5

       36
Timetable (if known)              
Private Study 114
TOTAL HOURS 150

Assessment
EXAM Duration Timing
(Semester)		 % of
final
mark		 Resit/resubmission
opportunity		 Penalty for late
submission		 Notes
Written Examination  3 hours  second  80  August    The examination will: (1) allow students to demonstrate an understanding of transition-metal chemistry, (2) test students' problem-solving skills in various aspects of transition-metal complex chemistry. (3) test students' ability to construct cogent arguments.  
CONTINUOUS Duration Timing
(Semester)		 % of
final
mark		 Resit/resubmission
opportunity		 Penalty for late
submission		 Notes
Tutorial attendance and written work  5 x 1-hr sessions  second  10  none  1 mark for tutorial participation.  1 mark for satisfactory work completion. No mark if tutorial work not handed in on time, unless written evidence is forthcoming. This work is not marked anonymously  
Extended Problem Set  own time  second  10  none  5% deduction per working day after the published deadline upto a max of 5 working days.  Work received more than 5 days after the published deadline will not be accepted without the timely submission of appropriate documentary evidence approved by the module leader. This work is not marked anonymously  

Recommended Texts

Essential:

“Chemistry” C.E. Housecroft and E. C. Constable Prentice Hall, Harlow, 2002. ISBN(paperback) 0130869244

Additional Sources:

 D.F. Shriver and P.W. Atkins, “Inorganic Chemistry” (3 rd Edition), OUP Oxford  1999, ISBN (paperback) 0 19 850330 x.    (This comes with a CD-ROM containing manypictures used in the handouts for this course, together with other usefulmaterial.)

 “AdvancedInorganic Chemistry (Sixth Edition)” by F.A. Cotton, G.Wilkinson, C.A.Murillo and M. Bochmann (available in the Harold Cohen Library Undergradcollection).

 M.Bochmann’s “Organometallics 1” is recommended for Dr.Whyman’s lectures.  The latter makes a good introduction to “ Organometallics 2”, which is the coursebook for the third year organometallic chemis try lectures.