Hyperquad2008
Equilibrium Constants from Potentiometric Data
Written by |
| Peter Gans |
Protonic Software |
| Antonio Sabatini |
University of Florence |
| Alberto Vacca |
University of Florence |
Hyperquad2008 is a Windows™ application that can that can be used to
derive equilibrium constants from experimental data. The data are usually obtained
by means of potentiometric titration. Hyperquad2008 is the latest in a
long series of developments. The basis for the stability constant refinement
of an earlier version has been published: P. Gans, A. Sabatini and A. Vacca,
Talanta, (1996), 43, 1739-1753. 
(requires Acrobat reader). The 2008 version has many improvements and uses a
revised algorithm, making it more powerful
and reliable than ever before. For references to published papers see applications.
Principal modules
- Creating a new project. Experimental data are imported from a file. Supported
file formats presently include those produced by Titrino, Titrando, Tiamo,
Vesuv, SchottTR600, Timtalk and Titramaster software. Other formats may be
added on application to P.G.
- Editing the chemical model. There are no restrictions on the complexity
of the model.
- Interactive fitting of the data. The data are presented graphically and
the model is adjusted manually to obtain an approximate fit of the data. (Partly
illustrated above).
- Refinement of the stability constants. The refinement process is "live",
that is, the data in memory are updated at each refinement cycle. This is
a major improvement on previous versions which required the data to be saved
in a file before refinement..
- Viewing and reporting results. Results, tables and plots can be copied to
the clipboard for pasting into documents.
- Integration with the program HySS. One data file
can be used for both Hyperquad2008 and HySS.
Ancillary material
The package includes 6 sets of sample data, each one illustrating a different
type of calculation. The files are located in the folder \SAMPLES inside the
folder where Hyperquad was installed.
| |
Reagents |
Data type |
Comments |
| Sartrigly |
2 |
pH electrode |
Protonation of a dibasic acid |
| Ni gly |
3 |
pH electrode |
Formation of metal-ligand complexes |
| Ni tpt |
3 |
emf electrode |
Formation of metal-ligand complexes |
| Ni Hs Pro |
4 |
pH electrode |
Formation of ternary complexes |
| Fe-Tiron-EDTA |
4 |
pH electrode |
Competition method |
| Batch data |
3 |
emf electrode |
|
An example of each of the supported data import file types is also included
in the \SAMPLES folder.
The Help file has detailed descriptions of all the program's functions. Context-sensitive
help is provided.
System requirements
Hyperquad2008 designed to run on a PC under the Windows95/98/NT/2000/XP/Vista
operating systems. There are no specific system requirements.
Ordering
For further details and information on how to obtain the program please contact
peter.gans@hyperquad.co.uk.
What's changed from Hyperquad2006
- New program structure. The whole program is written in VisualBasic6. The
code incorporates both the material that was previously located in a DLL and
the material that was in the FORTRAN module.
- Data are "live" when performing a refinement. On convergence refined
values are in memory. If a plot is showing it will be automatically updated.
Revert button to undo effects of refinement.
- Stability constants (b values, not log b)
are constrained in refinement to be always positive. If a stability constant
is persistently tending towards a negative value the refinement is terminated.
- If divergence occurs shift-cutting is explored - no Marquardt parameter.
Refinements terminate if shift-cutting is not successful.
- New routine for calculating free concentrations based on refinement of the
logarithms of the free concentrations. Eliminates the possibility of negative
free concentrations.
- New routine for creating a new project. Similar to a "wizard"
with facilities to import or create model, import data from file and set up
all variables.
- Single, improved, weighting scheme.
- Refinement output simplified. Better diagnostics in case a refinement fails
to converge.
- Tables of concentrations, observed/calculated data removed from refinement
output. The tables are available from the main window at all times.
- Extended selections are now possible in some tables, by dragging the mouse
over the selection.
- Legacy data in PAR and PPD files or Superquad files have to be imported.
- Some options have been removed. If one of these options is required, Hyperquad2006
is still available.
- Potentiometric data only. For spectrophotometric data use HypSpec.
- Oxygen as a ligand
- Redox electrode
- Two electrodes
- Refinement of standard electrode potential
- Constraints on dangerous parameters
- Model selector
- Different types of titration curve, e.g. ligand protonation and metal/ligand
complexation .
Stability Constants home page