What is practical importance of Kohn anomaly for experimentalists and/or theorists?
closed as not a real question by mbq♦ Nov 20 '12 at 13:01
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The practical importance of a Kohn anomaly is that it is a direct evidence of electron phonon coupling in a metallic system. This is used as evidence for electron-phonon coupling in BCS superconductors for example. Further, a Kohn anomaly is a sharp change in a lattice vibration that can cause a lattice instabilities, which can result in structural phase transitions of a material in extreme cases.