def addIterativeAcidPair(object1, object2, interaction):
    """
    Adding the Coulomb 'iterative' interaction (an acid pair):
    the higher pKa is raised  with QQ+HB
    the lower  pKa is lowered with HB
    """
    values = interaction[1]
    annihilation = interaction[2]
    hbond_value = values[0]
    coulomb_value = values[1]
    diff = coulomb_value + 2 * hbond_value
    comp1 = object1.pKa_old + annihilation[0] + diff
    comp2 = object2.pKa_old + annihilation[1] + diff
    annihilation[0] = 0.0
    annihilation[1] = 0.0
    if comp1 > comp2:
        determinant = [object2, hbond_value]
        object1.determinants['sidechain'].append(determinant)
        determinant = [object1, -hbond_value]
        object2.determinants['sidechain'].append(determinant)
        determinant = [object2, coulomb_value]
        object1.determinants['coulomb'].append(determinant)
        annihilation[0] = -diff
    else:
        determinant = [object1, hbond_value]
        object2.determinants['sidechain'].append(determinant)
        determinant = [object2, -hbond_value]
        object1.determinants['sidechain'].append(determinant)
        determinant = [object1, coulomb_value]
        object2.determinants['coulomb'].append(determinant)
        annihilation[1] = -diff
