Pairs of mass peaks
10B and
11B of the sublimated gas from the sample were measured successively at a rate of two pairs per minute throughout each experiment. The sample prepared by solidifying gas mixture of BCl
3 and Xe on a cold plate was irradiated for 20 minutes with a 3 W, 10.6 μm cw CO
2 laser to excite
11BCl
3 ν
3 vibration. After the irradiation, the sample was heated to promote the sublimation of gas from the sample surface. The out gas from the sample during laser irradiation is depleted in
11B, on the other hand the gas released by heating is enriched in
11B. This released gas is composed of two parts: the volatile with small separation factor 1.3 and the less volatile with large separation factor 15. The amount of these two parts of the product are estimated to be 0.21 and 0.14 mg respectively, which correspond to 7 and 5 percent of BCl
3 fed on the cold plate. This result obtained with a mass spectrometer is likely to support the previous conclusion from infrared spectral analysis: Selectively excited
11BCl
3 molecules migrate through Xe matrix to form crystalline
11BCl
3 0n the cold plate surface.
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