How to compute sound velocity in a solid

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1

Dear all,

I am going to compute sound velocity © in a simple argon solid. In the literature I found that c^2=dp/d(rho), but I don’t have any idea how to setup a MD simulation to obtain it.

Any suggestion would be appreciated.

Mohyeddin

2

Dear all,

I am going to compute sound velocity (c) in a simple argon solid. In the
literature I found that c^2=dp/d(rho), but I don't have any idea how to
setup a MD simulation to obtain it.

i think you need to expand your literature search a little bit.
already wikipedia has more detail to offer.
http://en.wikipedia.org/wiki/Speed_of_sound

axel.

3

There are lots of ways to estimate the sound speed, with subtle
distinctions between them. The cleanest way is to measure the elastic
constants at zero temperature. See script provided in
examples/ELASTIC. Other ways that are more complicated, but allow you
to distinguish adiabatic and isothermal sound speeds and other
effects:

1. Create a disturbance and watch it propagate
2. Measure stress versus strain