Abstract
\\
 Ab initio CCSD(full)/6-311++G(3df,2p) calculations were performed
for the bimolecular complex NH_3...H_2 and its rearrangements. The
ab initio calculations performed predict the existence of
sufficiently stable bimolecular complexes NH_3...H_2 with the very
small complexation energy of about 0.02 kcal/mol. 

A peculiar topology of the PES
is  found around a saddle point of index two.