On Mon, 28 Sep 2015 15:37:27 +0100 DesdeChaves wrote:

I try inserting several \chemical[ONE, .2MOV1] statements in some key places, but without success. Can you provide me a very simple example?

The idea is to draw the bond, then move, then the atom: \chemical [ONE,SB5,Z5,.2MOV1,Z0,.2MOV1,SB1,1.2MOV1,Z0] [H_3C,CH_2,CH_2] a bit sloppy, perhaps, but such is the syntax. On the other hand, one can make multiple calls to \chemical, thus making the code more readable. Alternately, one can shorten the bond segments which are defined as [.25,.75] of the bond length, but this turns out to be less aesthetic than adding small moves. One could imagine also to draw the text inside a framed box using a white background, as in \framed[frame=off,background=color,backgroundcolor=white]{\chemical{CH_2}} but I do not like this solution at all. I suppose that we could modify the underlying MP code to avoid extending any bond over the text box, but this would impose that the user draw the nodes before the bonds and would surely fail as one builds molecules in segments (unless the user be fully aware of the drawing process). We decided that this would be worse. Alan