next up previous contents index
Next: Initialization of the Hessian Up: Relax Options Previous: General Boundary Conditions for   Contents   Index

Special Boundary Conditions for Ahlrichs and Pulay Updates

For the default update method ahlrichs some additional control parameters are available which can be defined in this menu:
DEFINE BOUNDARY CONDITIONS FOR AHLRICHS OR PULAY UPDATE
--------------------------------------------------------------
option    | description
--------------------------------------------------------------
modus <i> | DEFINE MODUS FOR GDIIS PROCEDURE : MINIMIZE
          |  <dq|dq> IF  <i> = 0
          |  <g|dq>  IF  <i> = 1
          |  <g|g>   IF  <i> = 2
          |  <dE>    IF  <i> = 3
          | DEFAULT : <i> = 1
fail <r>  | IGNORE GDIIS IF  <g|dq> /| <g|dq> | IS
          | LARGER THAN -<r>. DEFAULT : <r> = 0.1
--------------------------------------------------------------
<RETURN> OR * OR q(uit) WILL TERMINATE THIS MENU
For detailed description consult Section 5.3.
--------------------------------------------------------------
OPTIONS FOR MANIPULATING THE HESSIAN
--------------------------------------------------------------
 option      | description
--------------------------------------------------------------
diagonal     | RESTRICT UPDATE TO DIAGONAL-ELEMENTS IF
             | METHOD IS BFGS,DFP OR MS. DEFAULT=n
offreset     | DISCARD OFF-DIAGONAL ELEMENTS. DEFAULT=n
offdamp <r>  | DAMP OFF-DIAGONAL ELEMENTS BY 1/(1+<r>) DEFAULT= 1.000
damp <real>  | DAMP UPDATE BY 1/(1+<real>), DEFAULT= .0000E+00
scale <real> | SCALE INPUT HESSIAN BY <real>, DEFAULT= 1.000
allow <real> | SCALE INPUT HESSIAN BY <real>/|DE| IF |DE|,
             | THE OBSERVED ABSOLUTE CHANGE IN ENERGY, IS
             | OBEYING THE CONDITION |DE| > <real> > 0.
             | DEFAULT : NO SCALING
min <real>   | DO NOT ALLOW EIGENVALUES OF HESSIAN TO DROP
             | BELOW <real>. DEFAULT= .1000E-02
reset <real> | USE <real> AS A RESET VALUE FOR TOO SMALL
             | EIGENVALUES (CP. min). DEFAULT= .1000E-02
max <real>   | DO NOT ALLOW EIGENVALUES OF HESSIAN TO BECOME
             | LARGER THAN <real>. DEFAULT= 1000.
--------------------------------------------------------------
WITH THE EXCEPTION OF min,reset AND max, ALL OPTIONS MAY BE
DISABLED BY ENTERING -<opt>
<RETURN> OR * OR q(uit) WILL TERMINATE THIS MENU



TURBOMOLE