We have introduced hydrogen into single crystal InP:Fe by implanting samples with 2 MeV protons and/or deuterons at fluences between 1×1016and 5×1017cm−2. This results in the creation of four local vibrational modes (LVMs) in infrared absorption which are all due to the stretching vibration of bonds formed between phosphorous and the implanted atom with various lattice defects or impurities at nearest‐neighbor sites. Our implant‐created LVMs are much sharper than those reported by previous workers and we observe two additional well separated peaks. The two main LVMs show a strong fluence dependence and are probably associated with lattice defects. The two weakest LVMs are not as fluence‐dependent and may be associated with impurities. Two samples were implanted with both protons and deuterons in an attempt to observe the formation of complexes containing both isotopes, but no evidence of such complexes could be found.