Infrared spectra of OCndash;HX hydrogenhyphen;bonded complexes in solid argon

摘要

The hydrogenhyphen;bonded complexes OCndash;HX (X=F, Cl, Br) has been prepared by condensing Ar/HX and Ar/CO reagent mixtures at 12 K. FTIR spectra of the complexes are characterized by strong Hndash;X absorptions (ngr;s) displaced below the isolated HX fundamental, strong Cndash;O absorptions displaced above the isolated CO fundamental, and sharp degenerate librational modes (ngr;l) in the far infrared. Observation of a single degenerate ngr;lmode indicates linear structures for the complexes. The displacements Dgr;ngr;sand Dgr;ngr;COfor the complexes decrease in magnitude in the series HFgsim;HClgsim;HBr in direct relationship with the trend in hydrogen bonding strength for the hydrohalic acids.