Symmetrization of the Dynamical Matrix for the Thermal Property Calculation

[ksauni]

Dear All,

Can I ask a question about the construction of the dynamical matrix with the force constant matrix?

To compute the thermal transmission coefficient with non-equilibrium green function (NEGF) method, the surface green function of the lead needs to be calculated and the off-diagonal part of the dynamical matrix is required.

On the other hand, I also heard that the dynamical matrix needs to be symmetrized so that the upper and lower triangle blocks in the dynamical matrix are hermitian conjugate to each other.

Would you please tell me how to symmetrize the dynamical matrix, which is built with the force constant matrix?

Thank you in advance.

Kind regards,

Kieran