[CPMD-list] Restarting interrupted TDDFT geometry optimization

[Salomon Billeter]

Dear Eung-Gun,

if you are using L-BFGS, restarting with HESSIAN has no effect on the
optimization because L-BFGS does not use or update any Hessian but
approximates the application of the inverse Hessian to the current gradient
from the history of displacements and gradients. This history, along with
the current trust radius, is read from the RESTART file using LSSTAT in the
RESTART line:
RESTART COORDINATES WAVEFUNCTION LSSTAT ADPTTL ...
ADPTTL will make CPMD read the status of the adaptive tolerance from the
RESTART file.
Still, the difference between the final coordinates should be normally very
small even if you don't read the mentioned information.

Best regards,
Salomon