Equilibrium Constants from Spectrophotometric Data

The Windows application HypSpec2014 is to be used for for the determination of equilibrium constants from spectrophotometric data. See HypSpec for details of the previous version.

IHypSpec2014 can process UV/visible, circular dichroism, infrared, Raman, luminescence and fluorescence data, subject to the single requirement that the spectral intensity of each chemical species should be proportional to the concentration of that species in solution. The spectral data may be obtained by titration or from a set of individual solutions (batch data). There is an option to include pH measurements in addition with both titration and batch data. For only potentiometric data use Hyperquad2013.


These references to precursor programs give the basic principles, but they are somewhat out of date as the algorithms have been changed extensively.

Hyperquad: P. Gans, A. Sabatini and A. Vacca, Talanta, (1996), 43, 1739-1753. view paper

pHab: P. Gans, A. Sabatini and A. Vacca,, Annali di Chimica, (1999), 89, 45-49. view paper


Experimental Data

A project can be created using spectroscopic data in

Help file

Sample data sets

  Spectral data alone Spectral data with pH measurements

Determination of a protonation constant in strongly alkaline solution
Metal-ligand complexes(3)

Metal - ligand complexes


Metal - ligand complexes in non-aqueous solution
Luminescence data

Polybasic acid

System requirements

HypSpec designed to run on a PC under the Windows XP, Vista, 7 and 8 operating systems. There are no specific system requirements,

What's new in HypSpec2014

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