ABSTRACT
An acid-base (donor-acceptor) interaction is a special kind of interaction involving one particle as a donor, and the other one as an acceptor of electron pair.
An acceptor is a molecular (atomic) system having unoccupied levels (orbitals) and a positive electron affi nity. A system having a lone electron pair is referred to as a donor. The electron pair becomes common for donor and acceptor when a bond is formed [4]. The forces of this nature are of our main interest.
