INTERACTION ENERGY CONTOURS OF MOLECULES AS PROBED BY A TEST ATOM

Potential energy contour curves for some simple molecules interacting with a test atom (a Li atom in the ground state) are calculated by the ab initio method. Relative hardness of the repulsive molecular surfac e is found to be anisotropic. This indicates that the outer boundary s urface of a molecule changes its form depending on the extent of appli ed external forces. The attractive nature of the molecular surface is demonstrated to be local. Surroundings of electronegative atoms having nonbonded electron pairs are found to be attractieve to the test atom having both electron-donating and electron-accepting abilities.