Geometry optimization

The geometry can be optimized by adding the GeoOpt key block. Within the block you can specify the maximum number of cycles and the convergence criterion. The optimizer works with Cartesian coordinates and a Quasi Newton stepper. The initial Hessian is simply the unit matrix. The GDIIS convergence accelerator is also implemented but is disabled by default. A geometry optimization can be restarted from a previous result (.runkf) file. The geometry can be optimized in the non-relativistic and scalar relativistic ZORA case.

References

Details about the theory of the analytical gradients within the BAND program can be found in

E. S. Kadantsev, R. Klooster. P. L. de Boeij, and T. Ziegler, Mol. Phys. (accepted for publication) (2007).