Infrared spectroscopy with a double modulation sideband technique

Both microwave and radio frequency modulation have been applied to CO/sub 2/ laser lines using only one CdTe modulator. As a result, a grid of closely spaced and tunable infrared frequencies is generated. This technique was used to perform infrared-infrared double resonance experiments on the molecules /sup 28/SiH/sub 4/ and /sup 28/SiF/sub 4/ and to observe the Stark splitting due to extremely small dipole moments. As a preliminary result, values have been obtained for several dipole moment parameters which agree with measurements performed with other techniques.<
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