Resources for Teachers

For animations look here: Animations

A good free app is IQmol, you can download it from here
  • they provide a server where you can run small jobs for free!
  • the app website has good resources for learning to use IQmol https://www.q-chem.com/
  • I'd suggest starting with this tutorial pdf
iqmol
If you want to start with some pre-optimised molecules first download these files and drag and drop it onto the IQmol blue window.
  • ammonia, NH3
    is a very important molecule in making fertilisers, today research chemists are looking for new catalysts to reduce the environmental impact of making ammonia
    iqmol_nh3
  • [emim]Cl
    is an ionic liquid ion pair, read about the new revolution in liquid materials
    iqmol_nh3
I'm keen to add some more molecules to the list please do e-mail me if you have a molecule to suggest!
Here is a small activity you can do with ammonia and 2 related molecules
  • first build and optimise
    • a molecule of NH3
    • a molecule of NH(Me)2
    • a molecule of NHF2
    • already optimised molecules of NH(Me)2 and NHF2
  • question: what is the N-H bond distance, r(N-H), in each molecule?
    • NH3 1.006 Å
    • NH(Me)2 1.039 Å
    • NHF2 1.015 Å
    • changing the substituents on the N has effected the N-H bond distance!
  • take your optimised a molecule of NH3 and carry out a frequency analysis
    • look at all the vibrations of NH3
    • can you find one that looks like an umbrella opening and closing?
      yes vibration at 460 cm-1
    • can you find one that has all the N-H bonds expanding and contracting together?
      yes vibration at 3575 cm-1