Perhaps there is some other better place to post this question, but since "ConTeXt" has put quite some effort to be compatible with it and since I cannot subscribe to ntg-ppchtex: I've tried to draw some chemical formulas with PPCTeX and wasn't able to find any option, allowing to visualize sp2 hibridisation on ONE atoms (i.e. 120 degrees). It is possible to make some "approximation" (2,4,7 for example), but it looks far away from perfect - the angles should be EXACTLY 120 degrees in that case (the same goes for NEWMAN). (some other, but maybe more exotic problems include PH_3, NH_3 for example, not forgetting about water) H / P-H \ H - Does there exist anything that would make SB and other bonds in ONE extent to the center of atom (the centar atom needs not be specified if it is C atom); perhaps R? How may I draw '/\/\/' for heksane (with angle 109 degrees)? - How can I name only one atom in the ring? (with the other places being filled with lines) Thank you, Mojca Miklavec