Lewis Formulas in MS Word?

FWIW I finally managed to get the Chem4Word addin to work and I don't think it will help at all.

If you really just need a diagram for H2O then in my view, using a graphics package or Word's own drawing tools (I haven't tried) is probably as good a solution as any, and likely to be more portable to different formats (PDF etc.)

For H2O, You can get close, but with various forms of formatting problem, using either:
 a. text and some special Unicode characters or
 b. a table (I tried a 5-column, 3-row table) with some other special characters and formatting
 c. an equation (just about).

A problem with all of these is what happens when you use something other than Word to view them (e.g., you create a PDF, save as a web page, or even open in the web-based version of Word. A good example is the one I posted on my OneDrive - in Word 2007, the rendering of example (a) seems fine, but the display on the Online version of Word is not so good, and that's probably what you'll see when you follow the link:  http://goo.gl/ujEDGB

What you have depicted is a Lewis diagram/structure, not a mathematical formula. Word's Equation tool only supports the latter - it is not a diagramming tool.

You may be able to generate Lewis diagrams using:

• Chem4Word http://chem4word.codeplex.com/releases/view/132214

• Accelrys Draw http://accelrys.com/products/informatics/cheminformatics/draw/

• ACD ChemSketch http://www.acdlabs.com/resources/freeware/chemsketch/