AN INFRARED STUDY OF THE EFFECT OF SOLVENT ON THE SI-H STRETCHING VIBRATION.

The effect of solvents on the Si-H stretching vibration occurring at approximately 4.7 microns was studied. Forty-four different solvents, ranging from 1.8 to 40 in dielectric constant, and five silanes were studied. The silanes were triethyl silane, tricyclohexyl silane, diphenyl methyl silane, triphenyl silane, and tribenzyl silane. Triphenyl silane and diphenyl methyl silane were studied extensively in the paraffins pentane to hexadecane plus paraffin oil. It was concluded that solvent effects, even in the case of the non-hydrogen bonded Si-H group, are the result of many interactions, both specific and non-specific, and that no relationship exists which can satisfactorily correlate infrared shifts with any property or properties of the solvent alone. A consideration of specific solute-solvent interactions appears to be the most plausible way of explaining infrared solvent-induced shifts.