Stimulated Raman effect in some tetrahedral molecules.
Stimulated Raman spectra have been excited in liquid SnCl(4) and in methane gas making use of a medium high-power ruby laser. The spectra have been photographed by means of a high-resolution grating spectrograph. The Deltagamma value approximately nu(1) for methane was found to be 2916.605 cm(-1) +/- 0.012 cm(-1). No detectable pressure shift was observed over a range of gas densities from 3 amagat to 12 amagat. The stimulated Raman lines in methane are very sharp and only slightly broader than the laser line. In SnCl4 the first Stokes line consists of only a single component instead of the expected isotopic triplet. The half-intensity width of this line was found to be 0.5 cm(-1). At least 0.15 cm(-1) of this line-width must be due to the stimulated Brillouin doublet since the threshold is lower for the stimulated Brillouin effect than for the stimulated Raman effect. The stimulated Brillouin effect was observed with a Fabry-Perot etalon. Measurements of the Fabry-Perot patterns gave a value of 840 m per see for the velocity of sound in SnCl(4) at 27 degrees C.
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DH
Physics Department, The Pennsylvania State University, University Park, Pennsylvania, USA.
Wick
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RV
Wiggins
T A
TA