GEOMETRY Hessupd HessUpdate .. END
Hessupd
HessUpdate
Specifies how the Hessian matrix is updated, using the gradient
values of the current and the previous geometry.
The methods available depend on the optimization branch being used.
For both the old and new branches, the following options are available:
(i) BFGS : Broyden-Fletcher-Goldfarb-Shanno
(ii) MS : Murtagh-Sargent
(iii) FARKAS : Farkas-Schlegel, Eq. (15) and (16) of Ref.
[139]
(iv) FARKAS-BOFILL : Farkas-Schlegel-Bofill, Eq. (15) and (14) of Ref.
[139]
In the old branch, the following extra options are available:
(i) DFP : Davidon-Fletcher-Powell
(ii) FS : Fletcher switch
(iii) HOSHINO : Hoshino
In the new branch, the following extra option is available:
(i) BAKKEN-HELGAKER: Bakken-Helgaker, see Ref.
[219]
The default is BFGS for geometry optimizations.
