Chemical Structure Indexing
The Chemical, Astronomical, and Numerical Indexes in Inspec can be thought of as very specific controlled indexes. Chemical Indexing provides standardized ways for searchers to find important chemical structures and chemicals in specific roles within the document. Chemical Indexing was introduced to Inspec in January 1987 and is present in all files going forward. For files prior to January 1987, chemical indexing was contained in the uncontrolled index field and was discretionary. Chemical substances are indexed by one of three basic categories: element (/el), binary (/bin), or system with 3 or more components (/ss) with there also being a provision for filing additionally to one of four special roles: adsorbate or any sorbate (/ads), dopant (/do), interface system (/int), surface or substrate (/sur). Organic substances are not covered in the chemical index field, and instead are found in the uncontrolled index field.
Engineering Village sample record illustrating Numerical Indexing and Chemical Indexing