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Chemistry Resources



 
USING CHEMICAL ABSTRACTS
A Basic Guide

The Chemical Abstracts (CA) is the most complete guide to the chemical literature of the world, referencing more than 14 million documents since it was first published in 1907. This completeness means that you can search CA with confidence, knowing that you won¹t miss essential chemical information. The answer to almost any pertinent question pertaining to chemistry can be found through Chemical Abstracts. By defining chemistry broadly, CA also covers aspects of many other scientific disciplines such as biology, clinical medicine, physics, geology, engineering, and more.
 

  • Index Guide

    • Annual thesaurus providing subject headings and controlled vocabulary, cross-references and indexing notes for common, trade, or systematic name for a chemical substance. This cross-reference toll provides a guide to the Volume and Collective General Subject and Chemical Substance Indexes. Located on the Index Table.
     
  • General Subject Terms

    • Abstracts are indexed through keyword phrases selected primarily from the abstract text and document title. Keywords reflect the terminology chosen by the authors in a variety of specialities and countries. Controlled vocabulary is added to reduce the scattering of references over several terms.
     
  • Chemical Substance Names

    • The Chemical Substance Index provides a systematic CA index name for common and trade names of chemical substances. The index name identifies a specific chemical substance. The index is arranged alphabetically by index name. Entries in the Chemical Substance index also include text modification phrases, which describe aspects of the substance that were studied. Although helpful, the nomenclature of entries have been extended from IUPAC (International Union of Pure and Applied Chemistry) to develop names such that each substance receives a single name. Index names are built around a parent, generally the name of a structural skeleton plus a suffix denoting the principal group. The index name is invented so that the parent appears first in the name printed in the index. This practice allows substances with the same structural skeleton to appear near each other in the alphabetically arranged index. Substituents on the parent structure are listed next in the name. They may be followed by a modification that identifies a specific derivative (such as an ester) of the principal indexed substance.

    Stereochemical information appears at the end of the name. 
    Cyclohexanecarboxylic acid,  4-chloro-3-[2-(methylamino)ethyl]-. ethyl ether (1a, 3b, 4b)
    Parent Substituents Modification Stereo

  • Molecular Formulas


    • The molecular formula index provides CA index names, CAS Registry Numbers, and abstract numbers for chemical substances identified by molecular formula. Element symbols in the molecular formula used in the Formula Index are arranged according to the Hill system. For all carbon-containing compounds, C is listed first, followed by H (if present), and then by the remaining elements. Formulas for substances that do not contain carbon are arranged alphabetically by element symbol.

    Hill System: C, H, Br, Cl, F, I, N, O, P, S, Si, M.
  • Ring System Handbook. 1988 4 vols. plus supplement

    • Compound-locating index arranged by the number of rings in a structure, then by the size of the component rings in ascending order (e.g., 5,6,7). Elemental components are arranged in Hill order. Entries give CAS registry number, Ring File number, index name, molecular formula, WLN, and structure diagram. Shelved on the CA Index Table.
  • Author Names

    • The Author Indexes link names of authors, coauthors, inventors, and assignees to the abstract numbers of documents that they have produced. Since corporations are frequently listed as assignees of patent rights, these indexes include corporate as well as personal names.

    The names are listed alphabetical by last name. When the last names are identical, the order is alphabetical by first initial and second initial (NOT alphabetically by the letters in the first name). Abstract numbers and document titles are linked only to the first listed author of coauthored papers. Other author names are cross-referenced to the name of the first author.
     

  • Patent Numbers

    • Patent abstracts are indexed in the General Subject, Chemical Substance, and Author Indexes by subject, substance, or known inventors or assignees. The patent number index allow for searching both two approaches: the patent number is the first document abstracted by CAS on the topic; the patent number belongs to an equivalent document. Patent Number will be linked to an abstract number for the document, listing a complete history of equivalent foreign patents.

    The equivalent patent will be cross-referred to the patent number of the first abstracted patent.
    DE (Germany) 4122229 A1 (Original citation: 116:219715j German Patent)
    CA 2046122 AA (Cross-referenced Canadian patent)
    FR 2664294 A1 (Cross-referenced French patent)
    GB 2245600 A1 (Cross-referenced Great Britain patent)

    Prior to 1981, patent numbers were indexed in two separate indexes -- The Numerical Patent Index and the Patent Concordance. The Numerical Patent Index provided abstract numbers for those patents abstracted in Chemical Abstracts. Equivalent patent documents were linked to the abstract of the first family member of through the Patent Concordance.

    LSUPatents

    Understanding Chemical Patents: A Guide for the Inventor. 1978
    John T. Maynard (Washington, D.C. : American Chemical Society), 1978.
    Second edition: 1991

    QD 39.2 M38 1978 Chemistry Resources Stacks
    QD 39.2 M38 1978 Middleton Library Stacks

    ACS primer on understanding patents as an information source, the patenting process, records keeping, infringement, and terminology. With a glossary.

    A Note on Patents

    Chemical patents are covered thoroughly by Chemical Abstracts, which has separate patent indexes. U.S. patents are on microfilm and paper in the Middleton Government Documents and the CASSIS CD-ROM system there is a good starting point for looking up U.S. patents on any topic. Foreign patents and patent applications often found in Chemical Abstracts are more difficult to get hold of, but are available through CA, Inter-Library Services, and the U.S. Patent and Trademark Office, and commercial vendors. Ask Library reference staff for more information.

    LSU Libraries -- Patents and Trademarks.

    LSU Libraries information guides for Patent, Trademark, and copyright information.

    Home Page for U.S. Patent and Trademark Office.

    Definitions of patents and instructions for conducting patent searches.

    Indexes

    Chemical Abstracts. 1907 -

    Shelved in Reference Stacks; newest issues on Index Table.

    The premier indexing source for chemical, biochemical, and chemical engineering literature, covering over 12,000 journals and confernces, as well as technical reports, dissertations, books, and patents. There are two basic parts: the weekly abstracts issues, arranged by topics (each issue contains its own indexes), and cumulative semiannual indexes, offering access by chemical substances name, formula, general subject, and author. There are also Collective Indexes covering 10 - or 5 - year periods. Use the printed flyers available in the Library to learn the basics of searching the printed indexes.

    Other parts of CA to know about:

  • Index Guide.

    • Annual thesaurus providing subject headings and controlled vocabulary, cross-refernces and indexing notes for use with CA's Chemical Substance and General Subject indexes. Located on the Index Table.
  • Registry Handbook -- Common Names.

    • Annual microfiche listing of chemical names and synonyms that gives registry number and formula for nearly 700,00 compounds as indexed in CA. The Name Section lists substance names selected from the Registry nomenclature file. The Number Section lists, by registry number, the corresponding CA Index Name for use in the printed indexes, along with synonyms. Next to the online Registry file, this is the best place to find registry numbers for searching in CAS Online, or Index Names for searching in the printed CA indexes.
  • Registry Handbook -- Number Section. 1965 -

    • Printed cumulation of all registry numbers assigned by CAS since 1965, showing CA Index Names and formula for searching in the indexes. Check the annual update for cumulative changes. Shelved near the end of the CA index area.
  • Ring System Handbook. 1988 4 vols. plus supplement

    • Compound-locating index arranged by the number of rings in a structure, then by the size of the component rings in ascending order (e.g., 5,6,7). Elemental components are arranged in Hill order. Entries give CAS registry number, Ring File number, index name, molecular formula, WLN, and structure diagram. Shelved on the CA Index Table.
  • CASSI. 1994

    • Retrospective listing of journal titles, conference titles, and other printed sources abstracted by CA, listed by their established CA abbreviations. Appears every 5 years, with quarterly updates. Very comprehensive. Located on the circulation desk.

    Chemical Abstracts is available online after 1967.
    Available through Dialog/STN or by full-service searches.

    CA Volumes & Collectives

     

     
     
     

    ONLINE CATALOG

    Use Online Catalog to locate books and journals held by the LSU Libraries on this topic. To search by subject, use established Library of Congress Subject Headings from the red volumes near the terminals. Use the subject search feild. Relevant general headings include:

    Similar searches in the periodical index of the Online Catalog will help locate journal articles on these topics.


    For questions or comments about this page, please contact
    William Armstrong

    Chemistry Resources
    LSU Libraries | Louisiana State University
    Baton Rouge, LA 70803-3100
    Tel (225) 578-8875 | Fax (225) 578-9432
    Copyright © 1999 - 2009 LSU Libraries
    Last Updated: 2007