Elastic moduli and intermolecular forces

Now the response of the solid to balanced applied forces is governed by the slope of the F-r curve in the nei bourhood of the equilibrium separation Tq. For this part of the curve the force Fset up when the intermolecular separation increases by 8r (from the value ro) is given by  

Comparing equations [2.36] and [2.39] shows that 0 is equal to Eto on this model. Typically E is of the order of 10 Pa and ro is of the order of 0.5 nm, which gives a value of 50 N m for 0 and, using the expression for Pq gives a value of the order of 10 Hz for the Einstein frequency. 

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