Search for Species Data by Chemical Formula

Please follow the steps below to conduct your search (Help):

  1. Select any desired options for the search:
    than specified. (Help)
  2. Select the desired units for thermodynamic data:
  3. Select the desired type(s) of data:
    Thermodynamic Data      Other Data

Chemical Formula Search Help

Rules for chemical formulas (Back to search)

Examples of chemical formulas (Back to search)

Chemical FormulaSearch Specification
C2H4Species with two C, and four H.
CH2CH2Species with two C, and four H.
CH3CHSpecies with two C, and four H.
(CH2)2Species with two C, and four H.
C2H*F?Species with two C, zero or more H and one or more F.

Search options (step 2) (Back to search)

Exactly match the specified isotopes
When checked, this option indicates that the search should match isotopes as specified in the search formula. For example, when this option is not checked a search on H2 will match species containing deuterium and tritium atoms. If this option was checked, deuterium and tritium would be excluded from the search.
Allow elements not specified in formula
When checked, this option indicates that species containing elements not specified in the formula will also be matched. For example, a search for Te2 will find all of the species which contain exactly two tellurium atoms and any number of other atoms. Checking this option alone is equivalent to the "partial formula search" previously available from this site.
Allow more atoms of elements in formula than specified
This option indicates that species containg more atoms than specified of a given element will be matched. For example, a search for Te with only this option checked will find all tellurium, ditellurium, tritellurium, etc.
Exclude ions from the search
When this option is checked, the search will not match ions unless a charge is explicitly indicted in the formula.

Rules for data types (step 4) (Back to search)

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