It is shown that neutron scattering spectroscopy is a powerful technique for characterizing vibrations of hydrogen atoms in simple and complex transition metal hydridocarbonyls. The spectra of HCo(CO)4, H2Fe(CO)4, HMn(CO)5, HCo(PF3)4, KHFe(CO)4, H3Mn3(CO)12 and CsHFe3(CO)11 are recorded and discussed, and a neutron “selection rule” is used to assign vibrations in the first three compounds. It is found that the hydrogen bending vibration for a hydrogen atom in a three centre-two-electron bond, is little displaced from that in an ordinary bond.