MDL Chime

MDL Chime is a free plugin used by web browsers to display the three-dimensional structures of molecules.[1] It is part of the ISIS product line acquired by Symyx Technologies from scientific publisher Elsevier in October 2007. It is based on the RasMol code.[2]

Chime is used by a wide range of biochemistry web sites for the visualization of macromolecules. Many of these sites are linked to the World Index of Molecular Visualization Resources MolVisIndex.Org. Chime was also used until 2006 at the Protein Data Bank to examine structures stored there.

Although available in 1996 in both Windows 95 and classic Mac OS versions for both Netscape and Internet Explorer browsers, development of Chime did not follow the move to Mac OS X for the Mac and support for Windows-based browsers other than Internet Explorer was limited (although it works well in Mozilla Firefox). One significant feature added in 1997 was the ability to display spectroscopic data in the form of the IUPAC JCAMP-DX protocols. Apart from this, most updates since then were for the installation package to follow the development of Windows and Internet Explorer.

Chime largely has been superseded by Jmol, a non-proprietary open-source Java molecular visualization application/applet that has maintained most Chime command compatibility while adding features.

A feature of Chime which is not yet reproduced with Jmol is the calculation of electrostatic or hydrophobic potential for use in coloring molecular surfaces. Instead, Jmol relies on this data being provided by other calculation packages. Chime involves some level of calculation of these properties.

Now Chime is owned by Accelrys, and has been merged to Discovery Studio.