Molecular area of adsorbates

[Gurp <gurp $#at#$ pml.tno.nl>]

 Dear Netters,
 We are looking for a program that calculates the area of a molecule,
 which is projected on a surface. The practical background is the
 following: consider molecules that are adsorbed on a surface. What is
 the average area they occupy on that surface ? This depends of course on
 how a particular molecule adsorbs on a surface, i.e. its orientation
 relative to the surface. As a first estimate one may take the average of
 a certain number of projections (or cross sectional areas). Does anyone
 know of a program that calculates such projected surfaces from a MOL,
 XYZ, PDB or QUANTA MSF file input, or, even better, a program which also
 takes into account the preferred orientations of a molecule on a surface
 ?
 I will summarize your reactions.
 Thanx,
 Ronald A. van Gurp
 Prins Maurits Laboratory TNO
 P.O. Box 45
 2280 AA Rijswijk
 The Netherlands