15.2 evib features

The evib module, implemented in TURBOMOLE, allows to calculate the matrix elements of the first order derivative of the Kohn-Sham operator with respect to atomic displacements χ

which are required to obtain the first order EV coupling constant, as given in Eq. above [181].

Features and limitations:

• LDA, GGA and mGGA functionals supported,
• RHF and UHF,
• SMP parallelization,
• only c1 symmetry at the moment,
• derivatives of the quadrature weights are not supported, use of large grids recommended,
• just direct calculation, no ri-approximation at the moment.