The structures of halogen atom-benzene complexes were investigated by modern DFT and ab initio computational methods. The spectroscopic properties of the complexes are also predicted and are in good agreement with experiment where such data have been reported. The fluorine atom-benzene complex is predicted to be a a complex due to the strength of a C-F bond. The chlorine atom-benzene complex is predicted to have an eta1 pi complex structure, which is only slightly more favorable (1.1 kcal/mol with the BH&HLYP/6-311++G** method including the ZPE correction) than a a complex but is significantly more stable (4.4 kcal/mol with the BH&HLYP/6-311++G** method including the ZPE correction) than the 116 T complex. The bromine and iodine benzene complexes are also predicted to prefer an eta(1) pi complex structure.