link_cell_neighbour_index(moldyn,
(btom->r.x+moldyn->dim.x/2)/lc->x,
(btom->r.y+moldyn->dim.y/2)/lc->y,
(btom->r.z+moldyn->dim.z/2)/lc->z,
neighbourk);
link_cell_neighbour_index(moldyn,
(btom->r.x+moldyn->dim.x/2)/lc->x,
(btom->r.y+moldyn->dim.y/2)/lc->y,
(btom->r.z+moldyn->dim.z/2)/lc->z,
neighbourk);