- #1

AngelFis93

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- Homework Statement:
- It's stated on an example problem that under Debye aproximation on a monoatomic cubic lattice of lattice constant a= 3.7 Å, sound speed v=3000 m/s (in both longitudinal and transverse directions) and Debye frequency ω=3.2·10^(13) rad/s, to find the minimum phonon wavelength. They give you the solution λ=4.27 Å .

- Relevant Equations:
- λ=v/f

Since in Debye aproximation Debye's frecuency is defined as the maximum frecueny , the corresponding wavelenght should be the minimum one, due to the inverse relation among those

λ=v/f=v·2π/ω=5.9 Å , which is higher than the given result.

I believe I should be using the information 'cubic lattice' somehow ,but can't see it.

Thanks.

λ=v/f=v·2π/ω=5.9 Å , which is higher than the given result.

I believe I should be using the information 'cubic lattice' somehow ,but can't see it.

Thanks.

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