g elements
            int.elem1 = p1;
            int.elem2 = p2;
            
            % Create binary kinematic object
            kin = this.createPPKinematic(p1,dir,dist,separ);
            kin.setEffParams(int);
            int.kinemat = kin;
            
            % Add references of new interaction to both elements and global list
            p1.interacts(end+1)  = int;
            p1.neigh_p(end+1)    = p2;
            p1.neigh_pid(end+1)  = p2.id;
            p2.interacts(end+1)  = int;
     