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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
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option    | description
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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
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<RETURN> OR * OR q(uit) WILL TERMINATE THIS MENU
For detailed description consult Section 5.3.
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OPTIONS FOR MANIPULATING THE HESSIAN
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 option      | description
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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.
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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



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