We propose a photodetachment scheme for observing interference effects
caused by the simultaneous action of a two-color low-frequency field
with commensurate frequencies during the photodetachment event, By cha
nging the relative phase of the low-frequency fields, considerable mod
ifications are found to occur in the angular distributions of the phot
oelectrons as well as in their energy spectra. Some properties of the
photoelectron angular distributions are discussed, and the extension o
f the energy spectra as a function of the low-frequency radiation para
meters is evaluated. [S1050-2947(98)50101-1].