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A chemical file format is a type of data file which is used specifically for depicting molecular data. One of the most widely used is the chemical table file format, which is similar to Structure Data Format files. They are text files that represent multiple chemical structure records and associated data fields.
Chemical table file (CT file) is a family of text-based chemical file formats that describe molecules and chemical reactions. One format, for example, lists each atom in a molecule, the x-y-z coordinates of that atom, and the bonds among the atoms.
Chemical file format; C. CCP4 (file format) CDX Format; CDXML; Chemical Markup Language; Chemical table file; Crystallographic Information File; H. Hierarchical ...
The PDB file format was invented in 1972 [2] [3] as a human-readable file that would allow researchers to exchange the atomic coordinates in a given protein through a database system. Its fixed-column width format is limited to 80 or 140 [ 4 ] columns, which was based on the width of the computer punch cards that were previously used to ...
Screenshot of the CAS Common Chemistry database with information about caffeine ().. A CAS Registry Number [1] (also referred to as CAS RN [2] or informally CAS Number) is a unique identification number, assigned by the Chemical Abstracts Service (CAS) in the US to every chemical substance described in the open scientific literature, in order to index the substance in the CAS Registry.
Chemical Markup Language (ChemML or CML) is an approach to managing molecular information using tools such as XML and Java. [1] It was the first domain specific implementation based strictly on XML , first based on a DTD [ 2 ] and later on an XML Schema , [ 3 ] the most robust and widely used system for precise information management in many areas.
For example, a chemical database might store a molecule with stereochemistry unspecified, whereas a chemical registry system requires the registrar to specify whether the stereo configuration is unknown, a specific (known) mixture, or racemic. Each of these would be considered a different record in a chemical registry system.
All analytical procedures should be validated. Identification tests are conducted to ensure the identity of an analyte in a sample through comparison of the sample to a reference standard through methods such as spectrum, chromatographic behavior, and chemical reactivity. [5] Impurity testing can either be a quantitative test or a limit test.