Author Topic: Phonon transmission calculations error  (Read 63 times)

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Offline Jyotirmoy Deb

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Phonon transmission calculations error
« on: January 21, 2020, 17:08 »
I have executed one phonon transmission calculations but unfortunately the calculation encountered an error showing an error message saying  "DynamicalMatrix calculations often require a tighter tolerance than the default".

Offline Petr Khomyakov

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Re: Phonon transmission calculations error
« Reply #1 on: January 22, 2020, 09:33 »
It is a warning, not an error. Using too low tolerance for total energy calculations might however give rise to large errors in Dynamical matrix, and your tolerance parameter is indeed pretty large, 10^-3, which is even larger than default value of 10^-4. I would set it to 10^-5.  In fact, one should check if Dynamical matrix does not significantly change when going, e.g., from tolerance of 10^-3 to 10^-4. If it does, one may even consider using 10^-5 to see if tolerance 10^-4 gives you converged Dynamical matrix.