Spectrophotometric Reference for Inorganics?

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Absorbance spectra and extinction coefficients for common inorganic substances, such as potassium and sodium salts, are often less documented compared to biological substances. Users express confusion about the capabilities of spectrophotometers, particularly regarding the use of Beer's Law for calculating salt concentrations based on absorbance measurements. There is uncertainty about whether certain salts, like sodium chloride, can be effectively analyzed with spectrophotometers, as some may not exhibit color or absorbance in the visible spectrum. The discussion suggests that absorbance spectra for these compounds should ideally be found in chemical handbooks or databases, with a recommendation to explore resources like the NIST Chemistry WebBook. Additionally, seeking original research papers may provide the needed data, although older studies might be more accessible.
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I am looking for absorbance spectra and extinction coefficients (molar absorptivities) for common inorganic substances like potassium and sodium salts. I am only finding this information for biological substances.

Am I misinterpreting what the spectrophotometer can do? I would like to, for example, use Beer's Law to calculate concentration of a salt in solution after measuring absorbance with a known extinction coefficient.
 
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Does the NaCl solution look colored?

Infrared? UV?
 
I mean salts in general, like potassium permanganate or copper (II) nitrate. I am unaware if sodium chloride can be used with a spectrophotometer; I was under the impression that some could not.

would like an absorbance spectrum (absorbance vs. wavelength), so all wavelengths. I would have thought this information would be tabulated somewhere, like a chemical handbook, but I am not finding it.
 
You can try here: http://webbook.nist.gov/chemistry/

Failing that you should just try to find the original research. It will likely be old which makes it (kind of) easier to find them for free.
 
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