.CML File Extension

A .CML file is a Chemical Markup Language File, created by N/A.

Open with Avogadro. Available for Linux, Windows, and Mac.

What is a .CML file?

The file extension .CML stands for Chemical Markup Language File. This type of file is an XML file specifically designed for the chemical sciences. The Chemical Markup Language (CML) is a standardized format used to represent chemical information, such as the structures of molecules or other data related to chemical informatics. This makes it a useful tool for the exchange and storage of chemical data.

A .CML file typically contains detailed descriptions of molecular structures, which can include the types of atoms, their positions, bonds between atoms, and other relevant chemical information. This data is structured in a way that can be easily read and processed by computers, facilitating its use in scientific research and education.

To ensure consistency and accuracy in the data stored in .CML files, the format follows a strict set of rules defined by a DTD (Document Type Definition) specification. This specification is contained in an .XSD (XML Schema Definition) file. Over time, multiple versions of this schema have been developed to improve and update the format as the field of chemical informatics evolves.

There are several software programs that can open and manipulate .CML files. These include: 1. **Avogadro** - A free, open-source molecular editor designed for cross-platform use, which provides tools for visualizing, editing, and simulating molecular structures. 2. **Bioclipse** - An open-source workbench for the life sciences. Bioclipse can manage and visualize molecular structures and other biological data. 3. **Open Babel** - Another free, open-source tool that is widely used for chemical data file conversion. It supports a wide range of chemical file formats, including CML. 4. **iBabel** - A graphical interface for the Open Babel software, designed to simplify the use of Open Babel for those who prefer not to use command-line tools.

These programs allow users to open .CML files, view the chemical structures contained within them, and perform various computational analyses or modifications to the data. This flexibility makes .CML files an essential part of modern chemical informatics and research.


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