The cooperativity of aerogen-bonding interactions is studied in open-chain (KrOF2)(n-2-6) and (XeOF2)(n-2-6) clusters. The formation mechanism and bonding properties of these clusters are investigated by means of molecular electrostatic potentials, natural bond orbital and noncovalent interaction index analyses. The small variation of average interaction energy from the pentamer to hexamer cluster reveals that cooperativity effects are almost completely saturated in the larger clusters. The cooperative effects in the clusters also make an increase in the average Kr-83 or Xe-129 chemical shielding isotropies and total spin-spin coupling constants across the aerogen-bonding. (C) 2016 Elsevier B.V. All rights reserved.