All entries for Wednesday 12 January 2005
January 12, 2005
Email explaining edit of powerpoint presentation:
As you can see its very late (or very early depending how you see it). Anyway I just got back to Uni today, moved in, and this evening have been working on this sodding presentation.
The amount of stuff everyone has produced is amazing, and the very rough cut came to 42 rammed slides long! A somewhat long 15 minute presentation!
I’ve been working for hours to prune it down, into what I feel may be closer to its final edited form – and working towards our remit of “WHY was Zewail awarded the nobel prize”. (I’ve done this, since no one else has got all the material and time is more than pressing on all of us and we’ve got to give this a good shot, so I hope I’ve done everyone and everything justice!)
Much has been edited down making them proper slides, instead of individual essays (had to edit a lot of my own this way too!) Obviously we’ll be reading more than what’s just on the slide – as we all will have prepared some notes beforehand, but cant really do anything until we know what slides we’ve got.
Since we have 1 working day (Wendesday) before our doomsday before Mackenzie on Thursday I suggest the following (which can be refined at a later date):
We all perform the part of the presentation we actually put together and researched, no-one will know it better! (And at such short notice that is very true).
Slides 1–5 Lucinda
Slides 6–9 Eleanor
Slides 10–17 Dave and Alice – please split up who does which bit
Slides 18–22 Tom
Slides 23- 27 Will
Also what follows is a summary of some of the more complex slides:
Slide 11 –
This is the reaction profile of a 3-step mechanism, going from products to reactants
The positions indicated in red show transition states, that are a non-isolatable species – these are at local energy maxima
The positions indicated in blue show reaction intermediates, these are isolatable species- these are at a local energy minima
The barrier with the highest energy is the activation energy
In order for a reaction to proceed the activation energy must be over come
This is some of the information gained from kinetic studies and
is one of the areas probed through the use of femtosecond lasers
Slide 12 –
First initiating probing pulse laser – excites sample and starts reaction
At a selected time interval the probing laser (that does not affect the sample, just monitors it) probes the sample – this is then detected
The secondary pulses continue giving information at pre-selected intervals (10x-15 s)
Slide 15 –
Potential energy curves showing ground state and excited state for NaI. The upper curve shows the molecule vibrations in excited NaI. When the distance between the sodium nucleus and the iodine nucleus is short the covalent bond dominates, while the ion bond dominates at a greater distance. The vibrations may be compared to those of a marble rolling back and forth in a dish. As the 6.9 Å point is passed there is a chance that the marble will roll down to the lower curve. There it may end up in the pit to the left (return to ground state) or fly out to the right (decay into sodium and iodine atoms respectively). (From Lucinda’s research – just an alternative to what you already have Dave – also replacement picture).
If for timing we have to loose slides I suggest the following be edited out:
Slides 4, 14, And a few from the further development section if necessary
We could meet after our pre-lab talk on Wednesday, (but I have to give tour guides at 12) and have a quick run through.
I really do hope this is ok – it has taken ages, please be honest in your appraisals.
Please find attached the full length, and the “Tom edit” of the presentations