FTIR spectra of waterndash;hydrogen fluoride complexes in solid argon. Evidence for inversion doubling in the HF librational modes of H2Ondash;thinsp;ndash;HF

摘要

Cohyphen;condensation of dilute Ar/HF and Ar/H2O samples at 12 K produces a number of sharp new infrared absorptions. The major species, which exhibits a strong 3554.7 cmminus;1band and two quartets beginning at 753.1 and 635.6 cmminus;1, is identified as H2Ondash;thinsp;ndash;HF. Isotopic substitution in the base submolecule changes the splitting in the latter multiplets and provides evidence for inversion doubling of the Hndash;F librational modes in the H2Ondash;thinsp;ndash;HF complex. The reverse complex HFndash;thinsp;ndash;HOH, identified at 3915.5 cmminus;1, exhibits a stronger interaction when HOH is replaced by DOD. Two Hndash;F stretching fundamentals, which show small D2O shifts, increased markedly on sample warming and are assigned to the 1:2 complex H2Ondash;thinsp;ndash;HFndash;thinsp;ndash;HF with an open structure.