To analyse melting due to the dissociation of dislocations, one starts with the energy H l o c as function of distance between two dislocations. An isolated dislocation in 2D is a local distortions of the six-folded lattice, where neighbouring particles have five- and seven nearest neighbours, instead of six. It is important to note, that dislocations can only be created in pairs, due to topological reasons. A bound pair of dislocations is a local configuration with 5-7-7-5 neighbourhood.