Jmol already calculates bond-lengths to decide which atoms are bonded according to distance criteria. It would be very nice to be able to output a list of these bond-lengths, sorted according to central bonded sites. For example, the output obtained from http://icsd.ill.fr/icsd/index.php?action=Bonds&id[]=72989
Then of course it would be an extra bonus to be able to output a list of the bond angles as well, as can be done from the above URL. Finally :-) if you have a list of bond lengths, it would be very useful for inorganic/ionic structures to be able to calculate the bond-valence sum around the different cations. This is simply the sum of the individual bond valences = exp((Ro-R)/B) where R is the bond length and Ro and B are parameters for given cation-anion oxidation states obtained from a look-up table such as http://icsd.ill.fr/icsd/help/valence.html The valence states would be extracted from the CIF file, as used for drawing ionic radii. (Actually in my calculation I have a self-consistency loop, which assumes intial valence states, calculates the valence sum for comparison, and then if it is significantly different, uses this new value as the supposed valence state to select new Ro and B parameters). The bond valence sum is a very important check on the correctness of a structure. If it unreasonable then almost certainly something is wrong (atom coordinates, disorder, stoichiometry etc...) Alan. _____________________________________________________________ Dr Alan Hewat, ILL Grenoble, FRANCE <[EMAIL PROTECTED]>fax+33.476.20.76.48 +33.476.20.72.13 (.26 Mme Guillermet) http://www.ill.fr/dif/people/hewat/ _____________________________________________________________ ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Jmol-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jmol-users
