Abstract
Precise measurements of the i.r. spectra of a number of carbonyl complexes have been made. The complexes, which contain metal–metal bonds, are of two types: (i) LMn(CO)5, LRe(CO)5, and LCo(CO)4, (where L = a metal system, e.g., Ph3Sn or Ph3PAu, and (ii) monosubstituted tertiary-phosphine derivatives of these complexes. The assignment of bands in the fundamental C–O stretching region has been based upon intensity and energy considerations together with binary combination data.