Transcript SC-Database - u

Title
The IUPAC Stability Constants
Database (SC-Database)
The definitive up-to-date collection of all significant
published metal-complex stability constants
Adjustment and
correction of stability
constants, and their uses
• Ionic strength corrections
• Temperature corrections
• Speciation
Summary
Background:
• Designed to contain all significant
published metal-complex stability
constants.
• Contains all data from the book
volumes published by Royal Society
of Chemistry and IUPAC, 19571974.
• Data from all significant journals,
1887 - 2003.
• PC computer-based (32-bit) with
very fast and user-friendly searching
and display routines..
Features:
• 21,500 references covering 8,600
ligands in 102,000 records.
• Searchable on any combination of
ligand, metal, reference or
experimental details.
• Data displayed, printed or recorded
in many ways.
• Interactive software is included for
speciation, ionic strength and
temperature corrections.
• A tool for industry, research and
teaching.
• Download sample files from:
www.acadsoft.co.uk
Output options
Instant access to other applications
Output can be sent to:
• Screen or to:
• Printer; Clipboard or Disk file
Metal and reference details
Ligand structure
Ligand details
Format can be:
• Single record
• Multiple records
Experimental details
Other data
Constants
Thumbnail graphs of:
Temperature dependence
Ionic Strength dependence
Output of multiple records to printer,
clipboard or disk includes full references
Searching by ligand
Ligands can be searched on any combination of :
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Empirical formula (or fragment)
Name (or fragment) - full name or short name
Any structure fragment
Ligand class (from 34 classes)
CAS-RN
Double-clicking
on an entry in the
ligand list displays
the structure and
other details
Searching can be:
• exactly as specified or
• matching from start only or
• from anywhere within the entry
Search results are presented as a list of ligands matching the search criteria.
Ligands required by the user are selected from this list
Searching by ligand (sub-structure searching)
Choose from:
• 10 pre-defined sub-structures
• use the built-in structure editor, EdChemS
• load a mol file (e.g. from Chem Draw or
Isis Draw) from disk
• load from a personal structure library
Match by:
• exact bond type
• any bond type
(to allow for resonance)
Here the sub-structure Calix..
has been selected
Ligand class:
Ligands are assigned within 34 classes
Once displayed, structures may be:
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saved as a mol file or
saved to a personal structure library
printed or
copied to the clipboard for use in other applications.
Searching by reference or author
About 14,600 authors are cited in 21,600
references from 750 journals and sources.
SC-Database may be searched on:
• year range or
• journal, (any fragment of name, volume or
page number) or
• author (any surname or name fragment)
SC-Database may also be browsed by:
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author or
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journal
Searching by metal ion
Metal ions may be searched on:
any of over 130 metal ions (e.g. Cu+, Cu++, Cu+++)
alkali metal ions
alkaline earth metal ions
lanthanide ions
alternatively compare constants for 2 metal ions
Searching by experimental details
Experimental details may be
searched by:
• medium
• words in comments
• temperature
• method
• K values
Can handle up to:
Speciation
• 12 components
• 28 species
• 3 solid phases
Species distribution curves
may be plotted as:
• percentage plots
• lg conc. plots
• lg S plots (when
insolubles present)
Beta values may be
adjusted in real time
Curves may be plotted as:
• a function of pH
• a function of any reactant (pL)
• as a pie-chart, recalculated interactively for any
pH/pL
Metal Comparisons
Stability constants of 2 metal ions may be
searched for ligands which co-ordinate
one metal preferentially:
e.g. to target 90Sr2+ in the body, ligands
favouring Sr2+ over Ca2+ may be
important.
The output lists ligands in order of the
ratio: lg K(Sr)/lg K(M2) for values are quoted
in the same reference.
Output is to a text file.
Temperature and Ionic Strength Dependence
Temperature and Ionic Strength
dependence may be calculated
from built-in routines (Davies and
van’t Hoff equations):
Alternatively ancillary
programs may be used:
•Ionic Strength using SIT or
Pitzer
•Temperature dependence
using extensions of van’t
Hoff:
Ionic Strength Dependence
Specific Interaction Theory (SIT) - SIT.exe
SIT.exe - a program to calculate log K for
xM + yL + zH2O = MxYy(OH)z + zH+
over the ionic strength range 0-5 m, given the SIT parameters
• has a database of many SIT parameters
• considers 12 background electrolytes
• interconverts molaRities and molaLities
• interconvert log K(c) and log K(m)
• calculates SIT parameters from pairs of IS – log K values
SIT.exe
Reaction:
Hg2+ + H2O =
HgOH+ + H+
Calculation of SIT parameters:
La3+ + F- = LaF2+
Pitzer corrections
Salinity
Program:
To calculate:
•Activity coefficients based on Pitzer
•Stability constants based on Pitzer
•Oxygen solubility against salinity
•Oxygen solubility against fluid composition
•pKw against fluid composition
WAC
program:
etc.
To calculate activity coefficients using:
•Pitzer equation
•Lin-Tseng-Lee equation
Corrections for Temperature Changes
Choice of 8
equations
Full statistical
treatment
Current Developments
• All significant journals publishing stability constants are being checked up to 2003
• Sub-structure searching has been included, together with a dedicated structure
drawing package (EdChemS)
• An edited sub-set of SC-Database has been prepared and is included with SCDatabase and with Sol-Eq.(Solution Equilibria; principles and applications). And
other packages.
• Ionic strength corrections using Specific Interaction Theory have been added.
• Dedicated routines for calculating temperature dependence, sea water equilibria
and other specialized applications are being included.
• An internet on-line system is under study.
Contact Details
Data collection coordinated by K.J.Powell
[email protected]
Database conflation and management by L.D.Pettit
[email protected]
Structure searching software by V. Solov’ev
[email protected]
Temperature dependence etc. by I Sukhno and V. Buzko
[email protected]
Database software and distribution by Academic Software
www.acadsoft.co.uk