Comment A simple explanation of the Cu effect (Score 1) 56
It is not that the Copper atom changes the helical chirality, it is that upon binding the systems undergo a biasing of one of the possible helical conformations.
When you oxidize/reduce the copper atom, the system undergoes a conformational change that is still chiral, but different in geometry, and thus it generates a different electro-optical response.
For more info, look at the web article I mentioned elsewhere. It is an initial report back when I was workging on my PhD at Canary's lab.
