Defined in ITER Default value 00001 kcalmole Basic Test Change in energy in

# Defined in iter default value 00001 kcalmole basic

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Defined in ITER. | Default value 0.0001 kcal/mole Basic Test Change in energy in kcal/mole on successive iterations is less than SCFCRT. | Exceptions: If PRECISE is specified, SCFCRT=0.000001 | If a polarization calculation SCFCRT=1.D-11 | If a FORCE calculation SCFCRT=0.0000001 | If SCFCRT=n.nnn is specified SCFCRT=n.nnn | If a BFGS optimization, SCFCRT becomes a function | of the difference between the current energy and | the lowest energy of previous SCFs. Secondary tests: (1) Change in density matrix elements on two successive iterations must be less than 0.001 (2) Change in energy in eV on three successive iterations must be less than 10 x SCFCRT. - 142 -
CRITERIA Page 9-2 9.2 GEOMETRIC OPTIMIZATION CRITERIA Name: TOLERX "Test on X Satisfied" Defined in FLEPO Default value 0.0001 Angstroms Basic Test The projected change in geometry is less than TOLERX Angstroms. Exceptions If GNORM is specified, the TOLERX test is not used. Name: DELHOF "Herbert's Test Satisfied" Defined in FLEPO Default value 0.001 Basic Test The projected decrease in energy is less than DELHOF Kcals/mole. Exceptions If GNORM is specified, the DELHOF test is not used. Name: TOLERG "Test on Gradient Satisfied" Defined in FLEPO Default value 1.0 Basic Test The gradient norm in Kcals/mole/Angstrom is less than TOLERG multiplied by the square root of the number of coordinates to be optimized. Exceptions If GNORM=n.nnn is specified, TOLERG=n.nnn divided
by the square root of the number of coordinates to be optimized, and the secondary tests are not done. If LET is not specified, n.nnn is reset to 0.01, if it was smaller than 0.01. If PRECISE is specified, TOLERG=0.2 If a SADDLE calculation, TOLERG is made a function of the last gradient norm. Name: TOLERF "Heat of Formation Test Satisfied" Defined in FLEPO Default value 0.002 Kcal/mole Basic Test The calculated heats of formation on two successive cycles differ by less than TOLERF. Exceptions If GNORM is specified, the TOLERF test is not used. Secondary Tests For the TOLERG, TOLERF, and TOLERX tests, a second test in which no individual component of the gradient should be larger than TOLERG must be satisfied. Other Tests If, after the TOLERG, TOLERF, or TOLERX test has been satisfied three consecutive times the heat of formation has dropped by less than 0.3Kcal/mole, then the optimization is stopped. Exceptions If GNORM is specified, then this test is not performed. Name: TOL2 - 143 -
CRITERIA Page 9-3 Defined in POWSQ Default value 0.4 Basic Test The absolute value of the largest component of the gradient is less than TOL2 Exceptions If PRECISE is specified, TOL2=0.01 If GNORM=n.nn is specified, TOL2=n.nn If LET is not specified, TOL2 is reset to 0.01, if n.nn was smaller than 0.01. Name: TOLS1 Defined in NLLSQ Default Value 0.000 000 000 001 Basic Test The square of the ratio of the projected change in the geometry to the actual geometry is less than TOLS1.

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