[BetterCallSaul]

I can't seem to find any data for the absorption coefficients of the Nickel(2+) ion at wavelengths of 530nm, 578nm and 640nm to be  used for the  Beer-Lambert law. If anyone has any websites where I can find this information to share it  would be  greatly appreciated.

Regards,
A clueless Chemistry Undergraduate

[marquis]

I've always seen some variation in coefficients, depending on the instrument
used and parameters selected.

Usually, the coefficients are calculated by running known standards and then
applying Beers-Lambert to calculate. 

Is this possible?  Do you have access to an instrument?

Good luck.

[Corribus]

The extinction coefficient will depend on the ligands.

[BetterCallSaul]

Usually, the coefficients are calculated by running known standards and then
applying Beers-Lambert to calculate. 

Ah, yes that helps a lot as in my  results I have a Mole fraction of 0 for NiS0₄.
The equation they have given me is Y [ = A_measured - (1-x)A_M ]

Am I right is saying that this means that at a mole fraction of 0, the measured absorbance value will be my extinction coefficient (A_M for that wavelength?

Thanks a lot  for the help.