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Researcher's Toolkit 2023: SciFinder-n

One-day workshop for graduate students in engineering and the physical sciences.

Accessing Scifinder-n

SciFinder-n (best link) Register first (use your Cornell email)  Scifinder-n help  Scifinder-n training

Content (Chemical Abstracts)

Databases in Scifinder-n

  • References (indexing chemistry related content from 50k journals, plus patents, dissertations, preprints, reference works)
    • Also includes Medline, ChemZent (older abstracts) 
  • Registry (194 million organic and inorganic substances, 70 million protein and nucleic acid sequences)
  • Reactions (144+ million organic and organometallic reactions, natural product synthesis, biotransformations)
  • Chemical suppliers (hundreds of catalogs)
  • Chemical regulations (150 inventories)
  • Markush (substructure coverage in patents)

Open access resources


Practical tips


  • Export references (pdf, rtf, ris citation format) 
  • Save search results, combine multiple results 
  • Save searches as alerts 

Substances, reactions 

  • Import structures (.mol files, universal format) 
  • Search from ChemDraw 
  • Export structures, suppliers, properties, reactions (tables)

Polymers in SciFinder-n

Polymers are assigned CAS Registry Numbers® based on:

  • Monomers
  • Structural repeating unit (SRU)
  • Manual registration (unknown/proprietary composition)

Search polymers by:

  • Polymer formula (tips below) 
  • Monomer structures (as separate fragments) 
  • Class or descriptive term 

Search tips

  • Use the Single Component filter to separate out mixtures (this will retain covalently bonded components as in polymers).
  • Further refine by Exact Chemical Structure of specific monomers to filter out structural isomers
  • Polymer searching webinar 

Searching by formula

Polymer records have unique formats for molecular formula, based on either monomers or SRU. Component formulas are expressed in Hill order (carbons, hydrogens, then other atoms in alphabetical order). 

  • Monomer Formulas: addition polymers and most condensation polymers include the formula(e) of the monomers within brackets and closed with an “X”
    • Homopolymers: monomer in parentheses with “x”.
    • Copolymers: monomers separated by dots in parentheses with “x”. 
  • SRU Formulas: structural repeating units of symmetric condensation polymers include the formula of the repeating unit within brackets and closed with an “N”
    • SRU: SRU in parentheses with “n”. 
    • End Groups: single molecular formula following SRU formula.