Record Display for the EPA National Library Catalog

RECORD NUMBER: 9 OF 11

OLS Field Name OLS Field Data
Main Title Predicting Chemical Reactivity by Computer.
Author Karickhoff, S. W. ; McDaniel, V. K. ; Melton, C. ; Vellino, A. N. ; Nute, D. E. ;
CORP Author Environmental Research Lab., Athens, GA. ;Georgia Univ., Athens.
Publisher c1991
Year Published 1991
Report Number EPA/600/J-91/293;
Stock Number PB92-124312
Additional Subjects Chemical reactions ; Computerized simulation ; Environmental effects ; Pollution ; Chemical compounds ; Molecular structure ; Physical properties ; Chemical properties ; Organic compounds ; Reaction kinetics ; Ecosystems ; Spectrum analysis ; Hydrolysis ; Thermodynamic properties ; Absorption spectra ; Ionization ; Reprints ; SPARC system
Holdings
Library Call Number Additional Info Location Last
Modified
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Status
NTIS  PB92-124312 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 02/24/1992
Collation 14p
Abstract
Mathematical models for predicting the fate of pollutants in the environment require reactivity parameter values--that is, the physical and chemical constants that govern reactivity. Although empirical structure-activity relationships have been developed that allow estimation of some constants, such relationships generally hold only within limited families of chemicals. Computer programs are under development that predict chemical reactivity strictly from molecular structure for a broad range of molecular structures. A prototype computer system called SPARC (SPARC Performs Automated Reasoning in Chemistry) uses computational algorithms based on fundamental chemical structure theory to estimate a variety of reactivity parameters (e.g., equilibrium/rate constants, UV-visible absorption spectra, etc.). The capability crosses chemical family boundaries to cover a broad range of organic compounds. SPARC does not do 'first principles' computation, but seeks to analyze chemical structure relative to a specific reactivity query in much the same manner in which an expert chemist would do so. Molecular structures are broken into functional units with known intrinsic reactivity. The intrinsic behavior is modified for a specific molecule in question with mechanistic perturbation models. To date, computational procedures have been developed for UV-visible light absorption spectra, ionization pK(sub a), hydrolysis rate constants, and numerous physical properties. The paper describes the logic of the approach to chemistry prediction and provides an overview of the computational procedures. Additional papers are in preparation describing in detail the chemical models and specific applications. (Copyright (c) 1991 SETAC.)