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A Second Example of MCD Data
Finding Shape Where There Seems To Be None
We mixed indole with d-camphorsulfonic acid1 to produce a sample for MCD acquisition that shows very little interesting structure regardless of the direction of magnet force.
The following two datasets show the individual results with the Olis magnet in either the foward or reverse position.
Forward MCD Collection
 MCD spectrum collected from indole and d-camphorsulfonic acid with the Olis Magnet in the forward position.
Reverse MCD Collection
 MCD spectrum of the identical indole and d-camphorsulfonic acid after the Olis magnet was rotated 180°, so that the magnet is now in the reverse position.
However, when subtracting the forward MCD from the reverse MCD, we cancelled the d-campho contribution to the measurement and "found" the MCD of the indole.
Shape Where there Was None
The result of subtracting digitally the reverse MCD data from the forward MCD data in order to cancel the normal CD and produce the 2MCD spectrum.
One must wonder...
How many samples have been considered invalid for MCD work, because only one direction of the magnetic field was used, due to the cumbersome large magnets used in MCD before today?
Footnotes
1) A CD standard with no magnetic field affects. When mixed with indole, d-camphorsulfonic acid obscures the normal spectral shape of the crystalline compound, shown in the previous example to have distinct forward, reverse, and subtracted MCD spectra.
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