Microsoft Does Chemistry … And Open Source

Before it was canceled, I wrote the feature Digital Briefs for C&EN. It was a collection of blurbs about new software, websites, and databases for industry and academics. I’m not sure how many people actually read what we here at the magazine affectionately called Diggies, but I’m feeling nostalgic today, so I’d like to point out the new Chemistry Add-In for Microsoft Office Word.

Published on March 22, this open-source tool, also called Chem4Word, enables users to insert chemical labels, formulas, and two-dimensional structures into their documents. It is based on Chemical Markup Language (CML), which means that data is stored behind those labels, formulas, and structures that can also be transferred to other formats and documents.

Microsoft says that the add-in can handle any molecule for which CML data exists and that it comes with several hundred common molecules. Users can also alter existing CML data files as needed with an editor included in Chem4Word. Isotopes and labels can be added, atoms can be swapped out, and bonds can be redrawn.

According to Lee Dirks, the director of education and scholarly communication at Microsoft, since its launch, the free Chemistry Add-In for Word—which is still in beta form—has been downloaded more than 80,000 times. Joseph Townsend, one of the developers of Chem4Word, says, “We have deliberately released the add-in early so that the community could see our approach and so that future development directions could be informed by the public.” He expects the add-in source code to be posted soon on Codeplex, an open-source project website hosted by Microsoft.

But before you rush to the Microsoft site and download the add-in, I should point out that users need either Word 2007 or Word 2010 to run it. Sadly, I operate in the Stone Age (or is it Bronze Age?—I’m not sure) and have only Word 2003, so I haven’t been able to try out Chem4Word myself yet.

Noting that a lot of academics also use Macs, I asked Peter Murray-Rust—a professor of molecular informatics at the University of Cambridge, an originator of CML, and one of the collaborators in developing Chem4Word—whether the add-in is available for those PC alternatives. “Not at present,” he says. But he emphasizes that the add-in is open source and “will be available to the Mac Word and Open Office communities.” He adds, “We can advise them on what needs to be done.”

This add-in also brings to mind Adam Azman’s open-access chemical dictionary for Microsoft Office and Open Office—something I wrote about in Diggies last year. Townsend tells me that Chem4Word doesn’t have that spell-checking capability yet, “although we see that this is a possible extension for the future and maybe someone in the open-source community will be keen to do so.”

Anybody out there among the 80,000+ who have already downloaded the add-in? Can you give us a review?

Author: Lauren Wolf

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  1. I find that it works OK, but there’s no help in terms of importing CML files from ChemSketch. I get what amounts to a security error, and there are no instructions for fixing it. I have examined the coding and can’t see any difference between the ChemSketch CML files and the ones used by the Chemistry Add-In.

    The add-on would be useful and helpful IF it was more user-friendly. Right now you apparently need to be a macro programmer to use it, and I’m not.

    The structures are a bit odd, and not really publication-ready. But they’d be great for what I want (educational applications), if I could get anything imported.

  2. @danberger, thanks for sharing your review. Microsoft is really trying to promote this add-in as an open-source tool, so I checked in with Joseph Townsend about your ChemSketch problem. He said that, although he doesn’t have that particular drawing program, you could post your bug on Codeplex here (, and someone can try to help.

  3. Attention!!!

    The add-in is BASED on CML. As usual Microsoft never use a pure standard.

    Do not forget to write your papers with LaTeX!! Is the only typographic system for scientific papers. Really you can write any type of document with book quality. If you want more information please visit (TeX User’s Group).
    There is a LaTeX graphic frontend : LyX (

    LaTeX runs on any OS and on any computer.

    LaTeX is based on TeX, the typographical system written 30 years ago by Donald Knuth (

    Best Regards,
    Tabaré Pérez