Hydrogen bonding interaction between HO2 radical and selected organic acids, RCOOH (RÂ =Â CH3, H, Cl and F)

- Interaction of HO2 with selected RCOOH (R = CH3, H, Cl and F) is studied.
- Global minimum geometry is planar with two strong H-bonds between HO2 and RCOOH.
- The calculated values follow a trend with electron donating behavior of R-group.
- Hydrogen bond donating ability of the HO2 radical plays a dominant role when R = CH3.
- For R = F, hydrogen bond donating abilities of both monomers are equally important.