Chemistry - Essentials
SciFinder - you will need to register if you do not have an account. Contains references to patents, conference proceedings, technical reports, dissertations, and articles, as well as chemical data (structures and properties) and reaction information.
Reaxys Has reaction, synthesis, and chemical data. Data comes mostly from the Gmelin Handbook (inorganic chemistry), the Beilstein Handbook (organic chemistry), and select patent classes.
PubMed Has millions of citations from biomedical literature. Will usually have to click “Find it! With OLinks” to get to full-text.
Web of Science The best curated scientific citation service – you can tell easily who cited an article in question within the Web of Science database. Also has good search capabilities for finding and analyzing an author's publications.
Other Essential Resources
The CRC Handbook of Chemistry & Physics Has data on the properties of chemical substances. If you have a basic question about a substance try here.
Visual Elements Periodic Table (RSC) Basic information about the elements.
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