1 / 20

The IUPAC Stability Constants Database (SC-Database)

Title. The IUPAC Stability Constants Database (SC-Database). The definitive up-to-date collection of all significant published metal-complex stability constants. Ionic strength corrections Temperature corrections Speciation. Adjustment and correction of stability constants, and their uses.

milek
Download Presentation

The IUPAC Stability Constants Database (SC-Database)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Title The IUPAC Stability Constants Database (SC-Database) The definitive up-to-date collection of allsignificant published metal-complex stability constants • Ionic strength corrections • Temperature corrections • Speciation Adjustment and correction of stability constants, and their uses

  2. 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, 1957-1974. 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 Summary

  3. Output options Instant access to other applications • Output can be sent to: • Screenor to: • Printer; ClipboardorDisk file Metal and reference details Ligand structure Ligand details • Format can be: • Single record • Multiple records Experimental details Constants Other data Thumbnail graphs of: Temperature dependence Ionic Strength dependence Output of multiple records to printer, clipboard or disk includes full references

  4. Searching by ligand Double-clicking on an entry in the ligand list displays the structure and other details • Ligands can be searched on any combination of : • Empirical formula (or fragment) • Name (or fragment) - full name or short name • Any structure fragment • Ligand class (from 34 classes) • CAS-RN • 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

  5. 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: • saved as a mol file or • saved to a personal structure library • printed or • copied to the clipboard for use in other applications.

  6. 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: • author or • journal

  7. 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

  8. Speciation • Can handle up to: • 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

  9. 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.

  10. 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 programsmay be used: • Ionic Strength using SIT or Pitzer • Temperature dependence using extensions of van’t Hoff:

  11. 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

  12. SIT.exe Reaction: Hg2+ + H2O = HgOH+ + H+ Calculation of SIT parameters: La3+ + F- = LaF2+

  13. Pitzer corrections • 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 etc. Salinity Program: WAC program: • To calculate activity coefficients using: • Pitzer equation • Lin-Tseng-Lee equation

  14. Corrections for Temperature Changes Choice of 8 equations Full statistical treatment

  15. 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 SC-Database 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.Powellk.powell@chem.canterbury.ac.nz Database conflation and management by L.D.Pettitlesp@acadsoft.co.uk Structure searching software by V. Solov’evsolvit@ipac.ac.ru Temperature dependence etc. by I Sukhno and V. BuzkoSukhno@chem.kubsu.ru Database software and distribution by Academic Softwarewww.acadsoft.co.uk

More Related