I suggest contacting Thomas Ferrin, who heads the Computer Graphics Laboratory
at UCSF. I have here a reference to:
...Based on earlier work in which we enumerated the types of data typically
found with computational chemistry allications [CoS90]
[CoS90] G. Chouch and D. Spellmeyer, "The MMWB Molecular Object Standard,"
Technical Report, Computer Graphics Laboratory, University of California, San
Francisco, CA, 1990.
In addition, you may want to take a look at their C++ (for gcc) class
"MolGraph" and it support classes "MolVertex", "MolEdge", and "MolRing" which
provide the functionality associated with molecular connectivity.
For farther information about that, see:
Unified Access to Macromolecular Data, Thomas Ferrin, Conrad Huang, Greg Couch,
and Eric Pettersen.
This paper is available via anonymous ftp to cgl.ucsf.edu in
/pub/otf-0.2.tar.gz . You'll have to gunzip and untar it, then
look in the doc directory.
Andrew Dalke
dalke at ks.uiuc.edu