Infrared spectra between 900 and 2000 cm^-1 of the EXP1 ice mixture (H₂O:CH₃OH:NH₃=10:1:1). The spectrum before irradiation was measured after 10 min of ice deposition at 25 K without photolysis. Afterwards, we started the simultaneous ice deposition and photolysis for 56h at 25 K. The two spectra are compared with pure ice of H₂CO, NHHCOO⁻, pure HCOOH, and pure NH₂CHO. ω is assigned to the broad band at 1710 cm^-1 that could be a combination of the HCOOH and NH₂CHO bands, whereas α is tentatively assigned to the bending (OH) of water.