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LEED of oxygen on Cu 110

OK ladies and gentlemen, I have been busy calculating the shape of the solid. With a copy of excel I have worked out where all the atoms should be and I have now drawn what the solid should look like. I used my trusty copy of ORTEP to generate a file which I feed into POVray. I will post  the picture in the next post.

What was happening in my experiment was that the clean copper 110 surface was reacting with oxygen to make a partly covered surface. I have drawn a surface which has a 100 % coverage. In real life it will not be 100 % covered.

The Langmuir model has the idea that a surface has a series of sites (all identical) these sites can bind to molecules. The coverage of the surface is given by the isotherm equation.

Coverage = kP/(1+kP) for physical absorption.

For a reaction of two gases say H2 and CO on a surface.

If the coverage of one substance goes too high then as no sites can now bind the other gas the reaction rate will go down. The rate of the reaction according to this theory is given by the equation

Rate = K(coverage 1)(coverage 2)

So when coverage 1 = 0.5 and coverage 2 = 0.5 then the reaction will be fastest.

I think that I have written plenty on heterogenous cats so I think it is time to move onto something else.

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