Anticooperativity in dihydrogen bonded clusters of ammonia and BeH42-

Ab initio calculations were used to analyze the interactions of BeH42- with 1-4 molecules of NH3 at the MP2/6-311++G(d,p) and B3LYP/6-311++G(d,p) computational levels. The cooperative effect is decreased with the increasing size of studied clusters. Blue shifts of the Be-H stretching frequency for complexes were predicted. The structures obtained have been analyzed with the atoms in molecules (AIM) methodology.