StatesOrthogonalization
StatesOrthogonalization
Section SCF::Eigensolver
Type integer
The full orthogonalization method used by some
eigensolvers. The default is cholesky_serial, except with state
parallelization, the default is cholesky_parallel.
Options:
- cholesky_serial:
Cholesky decomposition implemented using
BLAS/LAPACK. Can be used with domain parallelization but not
state parallelization.
- cholesky_parallel:
Cholesky decomposition implemented using
ScaLAPACK. Compatible with states parallelization.
- cgs:
Classical Gram-Schmidt (CGS) orthogonalization.
Can be used with domain parallelization but not state parallelization.
The algorithm is defined in Giraud et al., Computers and Mathematics with Applications 50, 1069 (2005).
- mgs:
Modified Gram-Schmidt (MGS) orthogonalization.
Can be used with domain parallelization but not state parallelization.
The algorithm is defined in Giraud et al., Computers and Mathematics with Applications 50, 1069 (2005).
- drcgs:
Classical Gram-Schmidt orthogonalization with double-step reorthogonalization.
Can be used with domain parallelization but not state parallelization.
The algorithm is taken from Giraud et al., Computers and Mathematics with Applications 50, 1069 (2005).
According to this reference, this is much more precise than CGS or MGS algorithms. The MGS version seems not to improve much the stability and would require more communications over the domains.