MadSci Network: Physics |
Molecular vibrations are indeed often in the 10s or 100s of terahertz regime. But remember that optical light has a frequency approaching a petahertz (10 to power 15), so molecular transitions typically involve fairly ordinary infrared photons, which could be studied with an infrared spectrograph, for instance. Whether matter melts (or vapourises) depends on the forces between the molecules. Although such frequencies sound incredibly high, the fact is that atoms and molecules have even more incredibly low mass (10 to power -27 kg for a proton), so electromagnetic forces (even if they are comparatively weak residual bonds such as van der Waals) may be enough to hold the molecules solidly.
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